<human>: Can you condense the text into a few key points?

So I met this girl a few semesters ago at my University and being the idiot I am I didn't try talking to her then. I am hardly on campus and dont have her phone number so the FB would have to be the primary communication method. How should I go about talking to her on FB? I never see her online but sometimes she pops up in my news feed. What would be the best way to start talking to her without coming off as a creep? also what should I talk about? I really wanna try to date this girl so all advice would be appreciated.
<bot>: I wanna talk to this girl via fb, I never see her online what would be the best way to break the ice and what should I talk to her about?