Crush adds me on facebook, what next?

This girl I have a huge crush at school, recently added me on facebook. I have a very small hunch that she might like me as well (she always seems to smile at me). I talked to one of my friends and told her that I had a crush on this girl, I'm guessing she told her and she added me... But I really don't know if she likes me or not because I never talked to her in real life. Well, I want to try, I want to know a good way to ask her if she likes me without being straightforward and what should I say first?