AlphaOmega's got the idea. Just confidently but not too obviously eagerly go up to her, perhaps shake her hand (firmly, but don't crush it -- actually the best hand shake ends with a sort of massage-like glide that subtly conveys mad physical skills), and say "Hi, what's up," or something to that effect. Then listen to what she has to say. Simple, really.
All the better to make good eye contact: sort of flirtatious, but relaxed (kinda hard to describe, but you'll know what I mean once you get the hang of it).
It's more about the "vibe" you convey than anything else. The main thing is just not to screw things up by trying too hard.