I want an orgasm

My boyfriend and I have been going strong an he is the first guy I've ever had sex with. I also don't masturbate, so I still am learning what an orgasm is.  I know I got one the first time we had sex, and then once more, but the vast majority of times I don't find myself experiencing one.  What can I do with sex or with my partner that will make me orgasm? Help a sister out