Directing her to the story section of this site can also be helpful to gague what she likes or to hint to her as to what you like.

When J and I first got together, it was in a good ol' vanilla r/l sense first (as opposed to the Lifestyle based relationships that a site like this often spawns). We both sensed that the other was inclined to play in a more BDSM related way, but neither of us had figured out a way to come right out and talk about it. It can be scary, as you well know. One day we were chatting on IM and he asked what I was doing. I said I was reading stories online and sent him the link to the Library section of this site. Within a few days I was tied up on the living room floor and things have been progressing nicely since then.

Good luck!