This could be satirical or not, but I figure this is good advice, with two threads I've seen in two days about this issue, I figured I could perform what amounts to a "public service announcement" about guys in general.
First thing you have to realize is that guys are dumb, clueless, and cowards, this is again in general, and since I'm a guy myself, I can insult "our side" all I want.

Knowing this, how do you get the proper attention from a guy? Actually its both easy and hard, it depends on the guy and on you, but one thing to realize is that if you "drop hints" they are most likely too subtle for him to notice. Even then, if he does notice the hints, you may end up confusing him.
The best approach is to be direct, you can do this in several ways, but the best thing to do is to make it unquestionable that you want to go out with him as a date, rather than a friend. This is important especially when you already are friends with him.
Guys have to be bashed over the head with a cluestick in order to actually get that you like them that way. I can give an example with my own experience. I was always shy, and back in high school, Sophomore year, a cheerleader was paying attention to me. I was on cloud nine, but still unsure that she actually wanted to go out with me. Yeah, I was stupid then, after several months of this, when I was sitting in the lunchroom one day, she actually sat down next to me, grabbed my hand, and shoved a piece of paper in my hand with her phone number on it, and then she just left. That was a big motherfucking clue, so I called her, we went out after that.
Guys like directness, we are actually quite simple in this way. Actually, there is one last thing, for the guys, women like directness too. There is always the risk of rejection, there is no getting around that, but life is too damned short to avoid having fun and obtaining happiness.