Scared to sit on his face

The title sums it up pretty well. I’m scared to sit on his face. He keeps asking me to and I’m nervous and he knows that so doesn’t pressure me, but he keeps asking.

I know it’s a totally normal thing but obviously I have insecurities like everyone.

Mostly concerned about being too heavy or any smell down there. Which is stupid to worry about cause he’s been down there a few times now and doesn’t seem put off.

Also I don’t really know how to gracefully get into that position.. any tips to doing this without crushing him whilst shoving my cooch in his face? (Gracefully is the key word)