First move?

My boyfriend says I never initiate anything or tell him when I want sex. But you see there is never a "good time" to say something. And idk how and I'm nervous. And he is right. He says we aren't having sex unless I make the first move and "seduce him". I need HELP. I've only ever been with one other guy. Idk how to do things or initiate things. I'm so nervous and I don't want to mess anything up. Please please give me some pointers here