My crush is hardly ever down here nd i really want to talk to him...?

my crush lives in ATL nd he's hardly ever down here,our parents know eachother but we've never been introduced,but nyway i found out through relatives they're going to be down here Sunday for Mother's Day nd i plan on talking to him at church,im not quite sure what to say nd everybody is always saying make eye contact and smile when you see him but i really do want to actually talk or even get his number or something because i dont know when he'll be coming back...ny suggestions on how i should do that? NO RUDE COMMENTS PLZ =)))) (p.s. we're both16)