Sit with her sometime when the two of you are not planning on being intimate and tell her you want to talk about making out. Ask her if she wants to talk about your love life, also. If so, then ask her what she likes, dislikes, would like to improve, and what she would like to try that you have as yet to do. Next--listen. He may divulge a lot of useful information.

Ask her about oral sex. How you approach the subject depends upon whether or not you have been doing it up to the point of ejaculating in her mouth, and, her personality. Some women don't mind giving it a try. Some do not want to, period; and, some like it or just do it as an accommodation.

The important thing for the man in this equation is that if she says she does not want to do it, that pretty much ends the discussion. On the other hand if she is worried about gagging or choking, then discuss how she can raise the tip of her tongue to the roof of the mouth and let the seman splatter against the bottom surface of the tongue thus preventing any bad reflexes.

The short of all this is, just talk.