How to ask a guy out to prom?

So i have liked this guy for a year now. we had 2 classes together last year and this we have one. We HARDLY talk :( i dont get a chance to talk to him at all. A while ago it was obvious to him that i liked him he told his friend "i think (my name) likes me" in fact on the firsst day of school he was smiling at me from across the hall and we always looked at each other in the halls but never really talked...but now its april and for the past couple months he's also hinted as if he is not interested in me. i get the feeling that he doesnt wanna be around me.I know hes told his friends that i like him.. anywayss..I REALLY REALLY REALLY wanna go to prom with him. Im afraid he will say no and I know i should ask him so i wont regret it later on but if he rejects me i'll feel like sh*t when i see him in class..its soo embaressing!!!!! oh and i heard he asked 2 asain girls out and they both rejected him..they said he was awkward ettc etc..soo idk what to do!!!!!! OH and this is senior year!! and ive never been to prom before..i have no date yet.