You should go up to him, and flirt with him basically. Do things like smile, look at him a lot, play with your hair, touch him often while talking to him, and give him open gestures like revealed palms. Give him complaments like he has nice hair, or whatever you like about him. Also try asking him if he's seeing anyone right now, and if he isn't say that you're suprised to hear that. If that doesn't work give him more intense flirting.. . If he likes you, he will look at you a lot, try touching you, smile, and basically flirt back. If he shows you these sings, but doesn;t give you his number ask him if he would like your's. If he is not intrested, you can tell if he looks away from you, smiles fakely; if at all, try to avoid you, and give you closed gestures like folded arms. If that is the case just move on.. . Whatever you do, do not tell him you like him because this will most likely scare him.