MY ADVICE
Don't Smoke - Its for people who think they are cool
Don't drink LOADS of alcohol - Nobody thinks someone is cool when they are sick over you (Drink a little if it gets your socialising though)
Don't do drugs - They are retarded
If you aren't good at sports etc, but want to get active, try running or cycling, everyone respects you later on for it ;D
Mate, your pic doesn't look bad at all, it's fine

Go out and have fun.