Dominating my boyfriend

So me and my boyfriend have been together for like 9 months and I love being dominanted like I’m very submissive and would do most things like tmi but I drank his piss the other night 😂 but I’ve just always been submissive but he told me the other night that one time he wants to be dominated and I really do not know what to do like even the thought makes me uncomfortable but if I knew what to do or how to act or what to say lol I think I’d be confident so can someone give me tips on what to say and do pls 😩😩 he said he wanted me to sit in his face and like ride him but idk how to portray these things or what to say