Ohhh I have this problem. Seriously, I spend most of my day thinking, talking, writing about sex, sex toys, sexuality and I can't dirty talk! lol
I have got a lot better at this recently by discovering that when I thought of dirty talk, I was thinking of it in the porno sense. Whenever a guy has talked dirty to me it was always the cruder the better in his opinion, I think. but it didn't do much for me.
Then I figured out that I don't have to unload a trail of swear words to be dirty talking. Thing is, with those words, you only have a certain amount to choose from and they get old quick. I now think of it as "Thinking out loud" rather than "dirty talking" and realise it can be so much hotter to sit and say things that are not outright rude or vulgar.
We have a little BDSM element going on, and me being in control helped me massively to start speaking. Like these ideas:
Asking questions:
Do you like it when I.....
How does it feel when...
Would you like me to put this in your...
And what would you like me to do to you....
Do you want me to touch you riiiiiight......here?
Demands:
Lay still
Shut up
Bend over
Beg me
Teasing or 'flippant' remarks:
You have/you are making my ...(Dick/nipples hard, pussy wet)
I bet you would love if if I just slid my fingers/tongue.....down.....here (Tracing your fingers downwards)....Oops, nope, maybe next time!
Well, don't you look cute all tied up and waiting. I like it. Maybe I should make you wait more!
Getting them to talk dirty to you (Genius!!)
Tell me what you want me to do to you
Tell me how it feels when I do.....this
What does it feel like inside my.....
You want to fuck me? Oh, Okay.....Tell me why you want to fuck me and I will think about it.
Describing the situation:
Do you know how much I love it when I see your....or when I hear you....or when I feel you.......(Insert whatever...throb, twitch, get wet, moan etc)
Its so hot watching you....
Every time I kiss you I feel your...
Etc etc. Then maybe when it gets more intense you can add a little more of the porno style "Yeh yeh fuck me ohhh yesssss" chat in there too.
I am still not great at talking dirty, but I just try to avoid talking dirty and aim for "Tease the crap out of him with some choice words and demands instead" method! lol