If you are close to someone as a friend and wanting to take it to the next level, then you should ask. "Hey Dave, we've been good friends for a while now and I would like to know if you ever think of us taking our friendship to the next level". The risk over course is that he may say no, but then you are in the same place you are now and if he says yes, then you can get on with the future relationship. - good luck to you. [next answer] 1]]Well, as a guy, I would say that we tend to talk to you more often, joke around ALOT more than with other people, and are just (at heart) nice to that person. Hope it helps!
2]] I actually have a friend who I like as more than that, so I can speak from experience that happens everyday. (The LTR i just ended was also with someone who started as my best friend).
-first, I can barely say "no" to anything she asks of me.
-second, If he stares at your body alot or he looks into your eyes for long periods of time with a smile cracking at one side of his face
-third, THIS IS THE GIVEAWAY!!! If he often initiates contact that its hard to define whether it was just platonic or mildly sexual.
-fourth, you should light up his day, no matter the circumstances (ok, i take that back, not ALL circumstances, but close to all) AND if you usually cheer him up instantly with your presence, and it didnt work, see if he approaches you for consolement about whatever is bothering him.