Interesting discussion being had here! Thought I would join in...
I have talked pretty openly about my sexual exploits with various women.
Two (what should be pretty obvious) things here:
1) She has to be open and comfortable enough about it, and;
2) You don't just bring it up out of thin air
If you get into a sexual conversation with a girl, then she's 9 times out of 10 not going to be put off by you telling her about experiences that you've had.
Just to give a couple more examples in addition to the ones that Drexel and Z provided:
1) I had a girl over for drinks and a movie once and the conversation turned sexual. I told her about something I had done to a girl, and she had me actually go get a pillow and a chair from the kitchen table to show her what I did. This actually got her laughing and turned on at the same time.
2) I was talking to a girl at a bar, and the conversation again turned sexual. Again, I was telling her about something I did to a girl and she had asked me something about how my hands were positioned, and I actually put one on her shoulder and the other on her side and said "like this".
The really cool thing is, you don't have to qualify yourself at all. Don't say something like "oh, she loved it and I made her cum like 15 times!", but you can just rather explain the encounter in a way that would seem appealing to her, and get her thinking about you doing these same acts to
her
NJ