Ahoy my advice would be to work on your eye contact, if you are doing it right she won't look away. (self plug imminent) I have bits on eye contact and forcing IOIs in my book. Anyways for the time being before you get your EC down I would suggest keep looking at her (obviously social smarts will tell you if you are being creepy) but most of the time she will look back, when you see her head turning turn yours so you both kinda make eye contact but it seems like you are looking around. Then just smile, laugh a little bit and look away ( anyone about to jump on me that it's not alpha, neither is bitching people out over forums about things that you don't understand yet

). So then jsut walk over (technically a warm approach as there is some semblance of rapport there already) and say hi.
Or if you fancy having some fun, tell her to stop undressing you with her eyes and jokingingly call her a pervert.
Anyways, work on your eye contact, ignore the bullshit about the 3 second rule (it's for people that haven't yet located their testicles) and don't try to make things perfect, pickup is like American football you can gain a yard, loose possession, generally fuck about and things not be perfect but keep pushing on and you will get yourself into the endzone lol