“Sit on my face”

I never loved the idea of my husband performing oral sex on me, but I’ve been thinking about it and now, years later, I decided I want to try again. The times he did, I was laying. I read recently about someone mentioning sitting on her husbands face…How does this logistically work? Lol 😂 it sounds like it would be difficult, but also sounds pretty awesome. Help? Tips and tricks? And is it really a turn on to come out of nowhere and tell him I want to sit on his face?