I don't think this is something you can learn from a script? I basically say what comes to mind, things I fantasize about. I guess you just need to think about what you enjoy. I personally like to hear my partner go into dirty detail about performing oral. "I'm going to start here and lick all the way to .... and put my tongue inside..." That sort of thing is what turns me on to hear. Everyone is different. Think about what turns your partner on and say those things. Some people like to say "spank me big daddy" and I personally could never say that without feeling real funny, so it's best to say what feels right to you, not someone else. Say the things that turn you and your partner on. That is all.

I bought a copy of the Penthouse Forum Letters and learned to read out loud from them. Then I swapped out their stories for my own fantasies and my ex loved that....

Writing the reviews also helped me to loosen up and let it out without being self conscious. Or a chat on sex chats....

it's nice to have material just to get some ideas. the letters sound like a good start.