So at some point, inevitably, your parents give you The Talk. The Big Talk. The one awkward, sometimes upsetting talk that initiates you into adulthood. Unfortunately for me, as the child of hippies, The Big Talk wasn't about the birds and the bees, but what we would do in the case of total nuclear annihilation, instead.

"As soon as they give the five-minute warning, we're pegging it to Wales," my dad explained. It was a sunny day in 1988, and we were in the back garden, mending a puncture on my bike. "Obviously all the other cunts will have the same idea, and the motorways will be rammed," Dad continued, fag wedged in mouth, "so we'll be taking the back roads. I'm thinking B4176 through Claverley. But once we get past Telford, we'll be fine."

"Oh, good," I said, carefully gluing the rubbery patch on to the wheel. I was glad we would be fine, once we got past Telford.

"Because most people will be dead by then," he explained, cheerfully. "Twenty per cent of the population gone with the first three bombs. POW! POW! POW! There won't even be any screaming. Not that you'd hear, anyway – because anyone within the 25-mile blast radius will instantly go deaf. Just keep watching the news, love. If the Soviets start getting arsey, pack a suitcase. Keep it under your bed. Best to be ready. We're only ever three bad days away from the start of Armageddon. Right, that's done," he said, standing up and looking at the bike. "You off to the library?"

"I suppose. While it's still there," I said, morosely. I'd got the new Terry Pratchett reserved, but it seemed rather futile to go and collect it now, given that I might die before I finished it. Perhaps I'd just reread Jane Eyre instead.

For another two years after this Big Talk, I fully expected the other Big Talk – The Sex Talk – to follow: either my mother or my father finally taking me to one side and telling me about sex. What it was, how to do it, and how I mustn't do it until I was 33, and happily married. But the talk never came. There was total radio silence.

I even tried to start it once: "So! Sex!" I said brightly. "What's that all about?"

"You've seen Bergerac," my mother replied, gnomically, closing the conversation down, to my infinite confusion.

And that was the end of that.

Now, 20 years later, I can only presume that this was because they presumed that a) I already knew what it was – perhaps, indeed, because of Bergerac – and they didn't want to patronise me, or b) they'd looked at me – fat, in NHS glasses, wearing an old tartan dressing gown instead of a coat, and apt to say "Forsooth!" when panicked – and calculated that, the cold war being what it was, I was unlikely to lose my virginity before the entire western world got wiped out, and it was a waste of their time – indeed, possibly taunting and cruel – to tell me about something I'd never get around to doing before I was vapourised. Either way, I never got The Big Talk.

But whatever your parents find too difficult to talk about, popular culture will invariably find fascinating. Mum and Dad may not have wanted to talk about sex, but telly, film, literature, newspapers and pop music did. As my hormones staged a coup over my life, I abandoned all other activities to became a full-time seeker of all the filth information out there. Thank you, world! Thank you for being full of rudeness!

I'd already grasped the basics, thanks to the joyous, posh fucking in Jilly Cooper's Riders and Rivals – generally very useful, albeit they made me believe champagne was an absolutely necessary part of copulation: either drunk, deployed in blow jobs, or just sprayed all over some hot nymphet splayed on a bed, who clearly didn't share a bunk bed with her sister, or have to worry about her only pyjamas (polyester, BHS, with a fetching teddy-bear print) having to be put in the wash afterwards.

However, all the information in Jilly Cooper novels was something I was just going to have to wait to deploy, when I got near some men. As a very self-motivated girl – I had, only the other week, made myself a poncho out of a tablecloth – I wanted to find out something about sex that I could get moving with. I wanted sex homework, essentially. Something I could practise, in my spare, man-less time, so that, when one finally got near me, I could spring knowledgably into action.

And this came when Twin Peaks was shown on British television in 1990. Although David Lynch's cinematography and meta-narrative yadda yadda… what I found truly interesting was the scene where the sexy teenage Audrey Horne (Sherilyn Fenn) applies for a job as a prostitute at Twin Peaks's spooky, high-class brothel, One Eyed Jack's. The owner asks Horne if she can prove she would be a good potential employee. Other sexy teenage would-be prostitutes might have replied by bringing out their CV, or perhaps talking about their Duke of Edinburgh's award. Or, frankly, just saying: "I have a vag." But Audrey Horne was far too sassy for that. She took a cherry from her cocktail, popped it into her sexy, red mouth and, 10 seconds later, carefully removed from the tip of her pink tongue the stalk, now tied in a perfect knot.

This scene made an enormous impression on me: I presumed that tying a cherry stalk into a knot was something all teenage girls had to master – up there with algebra, and how to fill in the paying-in slip on a Nationwide building society savings account – and decided to dedicate myself to learning this vital craft. I feared being at a party, some years hence, where all the other women were assiduously crocheting fruit stalks with their tongues, while I stood in the corner going, "So! Anyone know any great recipes using leftover mince? I do! BIG TIME!"

As cherries were far too luxurious an item to be on our family's shopping list – the only cherries I'd come across were the ones in tins of Del Monte fruit salad – I improvised with a piece of string, and spent long hours in my room, alone, quietly gurning as I tried to tie it into a knot with my tongue. Within a week I'd mastered the art, and was utterly triumphal – only to find that, within my house, there was a very limited audience for my sex skills.

"Do you need a poo?" my sister Caz asked, as I sat with her one night, quietly contorting my face as I worked on a particularly small piece of string. "You look like you're in pain."

When I exultantly spat the knotted string out into my hand, she looked at it and said, horrified, "Is that phlegm? There's what looks like a bit of lung in it. I think you have tuberculosis," and left the room with nose and mouth covered with her jumper sleeve.

"I'm practising being sexual!" I shouted after her. A younger sibling stared at me, then started to cry.

I would like to report that knowing how to tie a cherry stalk in a knot with my mouth did, one day, pay off – bagging me a handsome lover, who subsequently blew my mind. As it turned out, the only time I performed the trick with a man around was 20 years later, at the aftershow of an Eddie Izzard gig in Manchester, where I was with my sister Caz, standing by the buffet.

"Remember all those years ago, when I used to tie a piece of string in a knot with my mouth?" I asked her.

"Unfortunately, yes," she replied. "I'm still waiting for you to cough yourself to death, to be honest."

"I reckon I could take a piece of frisee lettuce from that salad," I said, pointing, "and tie that in a knot with my mouth."

One minute later, I proved my point admirably, as I ejected into my palm a piece of knotted lettuce. At that point, Eddie Izzard came up to us.

"I've tied a piece of lettuce in a knot with my tongue!" I told him, proudly proffering my bolus of veg and gob.

"And is that… useful?" he asked.

And I had to admit that today, and for more than 20 years, the answer had been, very much: "No. Not really. I mean, like, never at all."

So, by the age of 17, my interest in sex was still unabated. You know in memoirs by boys about being, say, football fans, where they talk about being captivated by the game at the age of 11, and by the time they're 17, they're travelling across the country dedicatedly to see York Town at every away fixture? I was like that – but with shagging.

By the time I was 17, I'd decided I wanted to be a great lay. A really amazing lay. "See her? She's a legendary piece of ass," I wanted people to say at literary parties while pointing at me.

This is the point where you might expect me to say, "But it proved very difficult – if not impossible." Traditional narrative insists that this would be the part where I would begin to struggle, against the odds, for decades, in order to fulfil my dearly held dream.

But that's because traditional narratives are written by boys – who do find it difficult to get laid. If you're a girl, on the other hand, you can get laid any time you like. Seriously. Fat, badly dressed, shy, awkward – not even actually in a room with a man at all – there is nothing that can be so "wrong" with a woman that she can't have sex any time she wants, merely by uttering this infallible, magic spell to a man: "Would you like to have some sex with me?"

And this is one of the things I like about men: they're uncomplicated. Sex is fun, they think, so I would like to do it whenever I can. Why not? It was certainly how I felt about it. Yes, sex can be a potentially risky activity for a woman, but I was in a fairly closed social circle, shagging colleagues and friends of friends, and for me, at least, it was less dangerous than riding a bicycle around town: I was still very shaky on the difference between "left" and "right", didn't understand the Highway Code and often got distracted if a pigeon flew past. I was much safer on top of a man than on a bicycle.

I quite liked the idea of gaining a lot of experience, and I was piqued by the fact that sex is the only skill where experience can be seen as a bad thing – for women, anyway. You would never denigrate a lady-plumber for having fitted over a thousand toilets, or a lady-pilot for having landed a thousand planes. Why, then – in a world of contraceptives, cheerfulness and feminism – was landing a thousand penises apt to have you titled a "slag"?

So I decided not to care about being called a slag – as a writer, I simply pressed "delete" on it in my head, knowing how easy to remove words ultimately are – and embarked on a two-year quest around London. And I have to say, it was all very interesting. It wasn't romantic, and the sex was often quite bad, but it definitely was – as all ardently pursued hobbies are – fascinating. Also, confusing. During my Sex Quest years – I used to refer to myself as a Lady Sex Pirate or Swashfuckler, in my head – I was given a lot of bewildering advice by men.

One man told me that the secret of being a good lay was: "Never let a hand lie idle. Always keep them both busy." Eager to show I was a good student, the next time we had sex, I noticed that one of my hands was, indeed, lying idle – and started to pat him on the back, absently, as if trying to wind a baby.

Another man at a party noticed I was fat, and proceeded to explain to me what fat girls are "like". "All fat girls," he stated confidently, smoking a fag, "are good at two things: swimming and blow jobs. Swimming, because they don't like any other sports, which make their boobies all jiggle around, and they like being weightless in the water. And blow jobs, because you don't have to take your clothes off."

I elegantly declined his later offer of "a poke" – "Soz, aqua-aerobics at 6am!" I said brightly, gathering my coat. "Gotta go and find my nose clip!" Additionally, that man smelled of ham. In a bad way.

But taking on board my newest dictum – that all experiences divide into a) Super Amazing Great Times or b) Awful Bad Times That Will Later Make Great Anecdotes – I'm still very happy that I had my two years of teenage rumpeteering. Dinner parties can be enlivened with the story of the pop star who passed out in my bed, leaving me confused as to what to do next. Eventually, I rang his tour manager, who sounded like he'd dealt with this situation before: "Just drag him into the corridor and leave him there," he said. "What room you in?"

"169 – but he's naked," I added.

"That's OK," the tour manager sighed. "We can dress him tomorrow."

And then there was the time I was with a man, and we decided to bring food into our "love-play", but all there was in the hotel mini-bar was a miniature packet of Pringles. This initially stumped us, until he remembered reading in a survival handbook that Pringles, due to their high fat content, make amazing firelighters. Utterly distracted, we then set fire to them one by one, marvelling over their steady, potato-y light, before just having some normal sex, without any food in it at all.

When I told these stories, my female friends started chipping in with their tales of being dirty teenage girls, too: how they were not shy, or tremulous, or scared, but bright, witty, horny girls going out and absolutely choosing to get about a bit, having sex with a man who made balloon animals, masturbating dementedly, trying out every perversion under the sun, and exploring the world through their genitals. And I thought, I'd like to write a novel about a girl like this. And then I did nothing about it.

Then Fifty Shades Of Grey got big. At first I was thrilled by the idea of it – an international blockbuster about a 21-year-old girl going at it hell-for-leather with a hot boy. "Hell, yeah, really dirty books for young girls," I thought. "Nice one, the 21st century."

But then I read the book, and completely changed my mind. For, by that point, one-in-three books sold that year were Fifty Shades, and the book had become a shorthand for female sexuality. If you were into sex, you were "a bit Fifty Shades". Female celebrities lined up to be quoted on their favourite bits.

But what I found in the book was a very niche corner of female sexuality being presented as an everywoman coming-of-age fantasy. Fifty Shades Of Grey is about a shy, studious, 21-year-old virgin who, in exchange for being repeatedly beaten on the clitoris with a hairbrush, gets an iPad and a go on Christian Grey's helicopter.

While I don't doubt – and am wholly for – this being what some women want, the monolithic place this book was taking up in young girls' sexual hinterlands I found disturbing. It's the opposite of independence, rebellion, curiosity, rock'n'roll and the carefully attended forming of your own desires. Anastasia is essentially a thoughtless, desireless, empty girl who has sex happening to her, via a powerful and unstoppable man – and I don't think I have to spell out why I find that sexual template deeply skeevy for, say, my own teenage daughter and her friends.

In short, although Anastasia Grey spends three whole novels being fucked every which way but Tuesday, this totemic shag book seemed to be the very opposite of everything I, and my collection of dirty female friends, recalled about our own sex adventuring years, and if I may be so bold and inappropriate, what I would want my own daughters to do, when the triumphant, unignorable clarion call of their genitals starts to rule their lives, in a few short years.

On top of all this, my dears, the solemn, unjoyous faff of it! The dungeons and linens and paddles and diets and doctors and waxing and waiting and whips and mind games. In a busy world that needs revolution, admin, inventiveness, glee and thrift, sex being depicted as a cross between the challenges on I'm A Celebrity… Get Me Out Of Here! and a trolley dash around selfridges.com seems like a deeply unnecessary complication. You know, sex is very simple. It's something cats manage to do on the shed roof, in the rain. You can make it complicated – but I've had some great times in a graveyard on a picnic blanket, and, indeed, up against bins around the back of a club – and I'd like something of that very British, make-do spirit to be represented somewhere in British sex fiction in 2014.

So, I wrote How To Build A Girl about a dirty teenage girl. Oh, it's not just about sex – it's about class, and pop music, and an odd love affair, and family. But I wanted to write something spirited and truthful and amusing about the two biggest words a girl can ever say – "Yes" and "No" – and about what happens when a virgin gets into bed with a much older man who's into S&M.

What I've actually done, I realised, even as I was writing this piece, is finally sit down and give the Big Sex Talk to my 13-year-old self. Here you go, babe. Hope you like it. Just one other thing – you don't end up marrying Han Solo. Sorry. But you also don't die a virgin in a nuclear holocaust – you definitely end up doing it. A lot. So it's swings and roundabouts .

• How To Build A Girl by Caitlin Moran is published by Ebury Press at £14.99. To order a copy for £11.49, with free UK p&p, go to theguardian.com/bookshop .