Orgasms During Sex...

So, I'm sort of having trouble with the whole coming thing when I have sex.. I don't really understand it because when ever me and my boyfriend start doing things I always get super wet. He always plays with my clit to turn me on and that feels good but when we start having sex it's not enough to make me come. So is there something I can do to make it more pleasurable for me? Or something he can do?