Try to avoid obvious fawning over him, you don't want to look needy. Get involved with things he is involved in so you meet up with him in a casual way. Then strike up a conversation, you are already both interested in the same thing(s) so you should have plenty to talk about (school, music, classes, mutual friends, hobbies, etc).
Go easy on the makeup, a survey done by one of the fashion magazines recently found that guys prefer natural looking makeup on girls. You don't want to frighten him with some wild or overly done makeup look. (Unless he is into Goth or that sort of thing, in which case, lay on that dark liner!!!) LOL
As already mentioned, just be yourself, guys can detect phoniness a mile off. Smile and speak gently and you are already there!