How do I talk about having sex for first time with GF?Watch
Non rapey attuned to her emotions and feelings doing.
You can talk about specific details / mechanics of sex. As part of a light hearted conversation. Or to get her thinking about sex as a way to turn her on. But don't talk specifically about her having sex with you, nor how you want to have sex with her.
As you don't want to come over as needy and desperate.