How do I tell this guy that I like him?

I just moved here, and my cousin is friends with this one kid. Anyways, I think that "Jimmy" might be gay..But how do I tell him that I like him? Is he even gay? He wears skinny jeans..And him and his bestfriend give each other piggy back rides and hug each other (we're almost 15) and when someone asks him if he's gay, he completely freaks out and yells at them..Are these signs? I sure hope so..Also, how do I tell him that I like him??