help please !

Katty
Well I'm really bad at communication and telling people in particular with my boyfriend what I want and I want to have sex with him but last time we did I wasn't ready 
And  I want to tell him and talk to him about it but I don't know what to say and I don't know how I feel about it exactly and I don't know it's just confusing and some I'm like I want to and then other days I'm unsure and yah I don't know I feel like there's more for me to say about it but I don't know how to either explain it or I don't know what the right words are and I hope it makes sense
I guess I'm just asking for tips on good communication and like good ways to express yourself and explain yourself and you have that like sex and stuff 
Thanks !