This next pocket of seven years will be bursting with things that will surprise, inspire and change you. There are some things however, that I'd like you to know now, just to make the journey ahead that little bit easier.
If you take just one crucial piece of advice from this letter, please let it be this. You are not old, and you do not know everything. Yes, you are on the verge of leaving school and will be going to the prom in a real, 'actual limousine with da bois.. OMG', (please stop talking like that), yes, your upper torso seems to have expanded into a mass of ample bosom (that doesn't mean excess mammary spillage is a good look though...), and yes, you're going to do pretty bloody well in your GCSEs, but in the grand scheme of things, you know only a tiny speck of dust upon an entire grand spectrum of information. Over the next seven years, you'll realise that learning is so much more satisfying when it doesn't end with a grade on a piece of paper. Learn as much as you can about everything that you can. Books are tonic for the idle mind; continue to immerse yourself in them. Appreciate creativity and literature and music and science and technology and religion and history and people and places. Appreciate everything, even the lesson on 'breeds of gulls' which may well be told to you by a half pissed, bearded old man on a train. If you never speak of it again, at least you will know which birdie is most likely to steal your tuna sandwich.
Please stop giving yourself that Lady-Sovereign-esque, scalp-chafing ponytail that sticks out of your head like a misplaced penis. It will get it's very own mention in the yearbook, and seven years on, you will still be mocked for it by all of your remaining school friends.
Keep your dignity when your heart gets broken. I can absolutely promise you that desperate, unsolicited, drunken text messages are never worth the humiliation. I can also absolutely promise you that although there will be times where you feel as if that one person has completely obliterated your one chance of heart-shaped happiness, you will move on. You'll eat a lot of pizza and you'll have a little cry and in a moment of rage you might even envisage yourself knocking them over with a tractor, but you will always move on; you're human, that's what humans do.
Love has a habit of fucking people up, but if you're drowning in the details of someone, it's always a risk worth taking. Just make sure they're kind. I fear that kindness is a dying art. Treasure those who champion it. (Also, show your Grandma a picture of every potential suitor and trust her instincts. She seems to have mastered the art of being right about these kind of things.)
Stop drinking blue alcohol in the park. It never ends well. Stay in and eat broccoli instead. Broccoli is awesome.
Keep writing. Don't listen to all of those people who will tell you to pursue a 'proper' career path. Always remember that whatever happens, and whatever you're getting paid to do, you are a writer through pursuit, not profession. You are a writer because you write. It will always be the greatest love of your life; honour it. And guess what? Your creative career will take off, eventually. From 2011 onwards, the Internet will become your literary playground. You'll have an audience. You'll write about life and genitals and the bizarreness of human beings, and people will actually read it. A French man will even tell you that you're the best thing to happen to the planet since Dr Who. Effectively, you'll also write yourself into a job that you love. Those soul destroying days behind the pizza counter at Asda will feel like a million years ago. Just don't accept that 'Transatlantic Agony Aunt' gig for the e-magazine in New York... That shit will get far too weird.
Fear is futile. Your hair looks terrible blonde. You're always going to be rubbish at looking interested when you're not. People you expect to live forever aren't going to live forever. Dinosaur onesies are totally okay. You're going to get a B in Art even though you are absolutely terrible at Art and everyone is expecting you to fail. (I know! That will remain perpetually funny.) Expand your horizons. Honesty is always the best policy, even when it feels like it's not. You'll always be your own worst critic. Wear heels that are comfortable; the intoxicated, stumbling goat look does you no favours.
Make the most of your blistering naiveity. These are the last few months of a beautiful pocket in time during which you are not fully aware of what the world is capable of. Don't waste it fretting about the size of your thighs.