me and my so are into S&M, but we both like being submissive

Me and my so are new to bdsm and we really like it, but we both like being slaves. He does an excellent job at being a master and I love feeling like his pet, but when I try to be a good master I don't feel like I'm doing a good job. I tie him up and torture him by teasing and not letting him cum, but I just don't think I'm a good master. I always feel awkward with talking dirty to him and he doesn't like to be spanked. I want to be a good dominant girlfriend but don't know how.