What turns a bi girl on?

I'm bi, but not openly. I'm so sexually attracted to one of my friends that is bi. We lightly flirt but I want it to be so much more. I wish I had the courage to just push her against a wall and kiss her and be exciting. But I don't have the balls to go that lol. So my question is what turns a bi girl on? What are something's I can do or say or act to have her entertain the idea of us doing that?

Well, think about what would turn you on. After all, you share the same sex and sexual orientation. It shouldn't be much more different, should it?
Plus, every person has their own little or not so little things that turn them on, so without knowing someone well enough, you can hardly guess what these are.

I hate to be obvious... but what about just talking to her or asking her out for coffee/tea, a movie, etc..