Need some advise about this girl I like.?

Ok, I really like this chick. She sometimes glances at me across the gym when I have her. Sucks cause I don't know her.I told her she had pretty eyes the other day and she said thank you but fast, is that good? And when I'm next to her she wobbles alil bit. Sucks cause I don't how to approach her without messing up and making a fool outta myself (I suck at starting conversations) I need some advise here. And I think she's the quite type or serious type? If that helps. And I'm not a girl, I'm a guy, just in case.