Maybe it would help to figure out what makes you uncomfortable, exactly? When I first started having sex, I was uncomfortable being on top too. Some of my reasons were being embarrassed about my partner being able to look up at my body and feeling self-conscious about my body; worrying that I didn't really know what to do up there and that I had to set the pace; and worrying that in the beginning, it hurt a little more than being on the bottom.

It really helped me to take it slow with a new partner. I tried starting with the lights off, or keeping my body closer to his instead of sitting up on top. I asked him to help me set the pace and rhythm by using his hands to push my hips. And it just got more comfortable over the time. But like I said first, the key for me was just having a partner I could communicate with about what was going on with me.