Tips for being on top plsssss

Claire • 22, in a relationship w a great guy🥰

So me and my boyfriend have been together for a few months and our sex life has been so amazing, but I haven’t gotten on top yet because I’m scared. I want to, and I know he wants me to too so that we can share the workload more. The things holding me back are mainly me being insecure about the way I look on top, I feel like I’ll look fat. Also I’m worried I won’t be any good. Does anyone have any advice? I want to start doing this within a week😅