How do I ask him to prom without being weird?

Hey everyone! I REALLY like this guy and I think he likes me to because he shows all the signs. But were not dating and one time in class we were doing work this one girl wanted to see his paper she was like let ya girl see it first he was like shes not my girl. And then she asked him were we gonna go to prom he was like shes not my girlfriend and she was like friends can go together he didnt say nothing, or at least I didnt hear him. The other day we were salsa dancing and his hands were sooo sweaty! And people like asked him were we dating and stuff he was like no were not. Even the teachers think we are. We did date once. Does it mean he wants to date me again!? Hes been to prom 3 times, and said it was lame. How can I talk him into going with me without being weird? How can I bring up the subject? I was gonna be like im so excited I get to go look at dresses this weekend. Would that be the perfect way? I mean hes always starring at me and smiling and touching me hugging me, hitting mein a fun way cause I hit him first but he gets mad about it He calls me annoying. Which im really not. How can I get him into me? Should I not talk about Danny Gokey around him? I have a HUGE dangerous obsession with Danny. HELP!!!