To me.

This is you from 13 years in the future. You might be thinking "WOW, COOL!!", but don't.
Seriously bro, you will mess up. You won't go to prison or anything like that, but it could heve been so much better. Just do as I say and you might end up better for it.
For starters, don't coast through school up to GCSE's. I know you can and I know that it's fun, but just dont. Second, don't do business studies GCSE. It sucks big ass. Do electronics instead, and instead of thet college IT thing, do geology.
Next, although you will work hard at A level, WORK HARDER. I know that it will kill you, but do it. Even if like me you choose not to go to uni, it will make your whole future easier and ultimately less stressfull.

Moving on from school, you must keep from adressing guys you just met as knob-ends and bitches. Sure it gets their attention and makes thyem think you're really serious... for about 5 minutes.
And have the balls to ask that blonde girl you will like out.
Lastly, don't drink that whole litre of cheap Vodka at your friends when you are 17. It will hurt for weeks.

Good luck. K.

P.S: IN a few years you will understand that by sending you this letter I have created a temporal paradox. If you follow my advice you will never need to send this letter, therefore your past self will grow up exactly the way I did, and send the letter, forming an infinite loop. Fun, eh!

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"Pop! Goes The Hamster....And Other Great Microwave Games"