Sex help.

Okay, so This guy I started seeing is like really kinky and just everything sexual wise I’ve wanted and like. But any time we go to start having sex I can get turned on but then I get to scared once he’s about to go in that I get unturned on, but I do it to myself. I’m not sure if it’s because i’m self conscious of myself so I get scared, or what. I haven’t had sex in 6 months and the kind I was having prior with me ex was just normal missionary with nothing mediocre type sex. Like I feel inexperienced compared to him and I’ve expressed that but like I just don’t know what to do. I want to have sex with him but i’m so nervous!! Can someone please give me some advice?!?!