How do you talk dirty to your boyfriend?

Connie
This is always a challenge for me. Every time we pleasure each other it's always so good but I know it would be so much better for him if i talked dirty in his ear. I know he likes it but for some reason, I get embarrassed, lack confidence to say what I really want to say. 
I loved to hear some of your thoughts and tips. 
How do you talk dirty to your man?