Yeah I was a virgin til a few months ago. I lost it with this great girl and we talked and she said she lost it at "19". Me being 21 and kind of intimidated at that I said at "19" also. Later she turned out to be my girlfriend and jsut recently I told her. She said she always thought of me to be a pimp but now shes likes me even more knowing that I'm not like that. It all depends on the type of girl your dealing with.
I can totally understand where your coming from. Its about trust, if you honestly dont feel you can trust her don't bother.
A few things to keep in mind are that sometimes girls are unpredictable with that information.
some things:
I know some girls who won't even date virgins (these ones tend to be *****es). One dumped the guy after he told her (she was hot but a total arrogant *****)
Sometimes girls are a little freaked out abnd uncomfortable if they know that they are going to be the first ones.
on a positive note:
Some girls respect and actually find it sexy that a guy isnt so easy to fyck every girl he can.
If she likes you enough, she won't care.
Overall I think you should just play it safe. Tease about her first time and if she asks you just say its a secret and smile. Let her imagination work.
I personally don't really know how to talk sexy. I just think talking lines is cheesy and id probably just end up laughing at myself. I usually just grab my girl around the waste and say "you look great tonight". Touching is better than words. Keep her smiling and touch her when you can and you will be alright.
Good luck man. You got nothing to worry about.