If you're not sure how to catch his attention, you could ask him things. Casually ask him what he's doing on vacation, when his next basketball game is, but not things to deep in emotion or too personal. That could creep him out and think you're nosy. And always be yourself, boys don't love girls that act all weird and strange around them. If you act fake, he may be let down when you start feeling more comfortable around him and "magically" turn into someone other than the person he met at first. Also, start finding things in common with both of you and talk about them so he notices them.
Steps
1. Smile. Remember to always smile if you get near him or see him once he looks at you. Remember to have a bright white smile and fresh-smelling breath when you talk to him.
2. Make the first move. Most girls don't think that they should, but it's usually worth it. A guy loves to know that a girl isn't so shy being with him and is setting a comfortable environment around him. A lot of guys consider this to be a really cool thing to do, as it takes a lot of the stress off of them.
3. Ask him a question. Guys love that a girl is actually the one who flirts with him first. Once you get to know him better, don't be afraid to start giving him hugs and such because it will help the guy know you like him.