How old are you again?
If you're old enough to be falling love, you should be mature enough to figure this out for yourself. If you just have a crush (and if you do I think you need to get someone to explain to you the difference between love and lust...and crushes) , then...here's what I'd do:
Firstly, make sure he likes you back. If he doesn't, well, you don't have much chance of being together, do you?
Second, if he does like you, make sure he knows you like him too.
Third, once you think he's picked up the vibe, tell him. Don't be afraid. Just find somewhere private, drag im away with you, tell him you like him, then walk away and let him think about it. I did this the first time I had a crush, and, well, it worked because he ran up to me and gave me a kiss on the cheek XD
Finally, if you can't get him out of your head, well...I dunno, cuz I'm having this crisis at the moment x.x
Good luck and I hope everything goes well.