What should I do to tell him how I feel?

Okay, I’m pretty sure this guy likes me.

My sister hates me being involved, because I don’t like dating. And everytime this guy does something to throw my interest, it never seems to work; I still like him anyway. I don’t know why though. Anyway, um, today in chapel, the speaker was asking who was going to homecoming. I was in the first pew, he was in the third; but we were both second to the end. I turned around, and we made eye contact. We lost it for a while, because I was focusing on my grades, and he probably didn’t think I was interested anymore, but we’ve since regained it again. He never talks to me, but I try to get in the conversation whenever I can. We were walking to chapel yesterday, and he was walking with another sort of friend (girl) of his… Oh, and today, I had to whisper something in his ear for this game “telephone” and I was pretty nervous, so I approached him, and his look was interested, as if he was looking forward to it. Nothing embarrassing happened, so yeah. I mean, everytime I look at him he looks down, but we used to be great with eye contact. He gets pretty nervous when I’m around too, and in biology, he used to scoot his chair closer to the table where I was sitting, and his shoulders almost always face me. When I walk through the halls, he mainly looks at me – hard to tell though. Tonight is the homecoming game – I’m not going. Neither to the dance, but I know if I did that would increase my chances of getting closer to him. But I’m too nervous, and my sister always suspects something. She thinks he could never like me, but I’m convinced he probably does. I’ve taken a good amount of quizzes, and all of them say he likes me. This is to confirm it, though. I think he’s too shy to do anything else, though. Although he’s pretty outgoing – I’m not in the popular group, and he is. Does he like me for sure? And what should I do to tell him I like him too? I think talking to him would be too much - especially since he’s almost always in a group or something.