Brush & floss your teeth.

 Drink milk! A lot of it!

 Don't be a jerk to those that love you. Hurting them will cause you to have a ton of guilt and shame.

 Don't start smoking.

 Start reading books. I know that it seems like labour now, but you will find magic.

 Eventually, you'll find that someone that likes you, all of you. Stop worrying about those that like you for just a single aspect of who you are.

 Get out of your little hometown as fast as you can. You will discover yourself when you are away from all you grew up with.

 Ask the girl in the red sweater out.