Femdom 101

Start slowly.

Don't be too ambitious.

Training your slave to lie still whilst you sit on his face could take weeks.
You need to be patient.
Tie his wrists to his thighs using old stockings (tightly).
Sit deeply and fully but allow that he will need to breathe periodically.
Initially, sit for about 20 mins but then increase it to 2-3 hours at a go.
Watching TV with friends is the best way to do this.

Your friends could be invaluable if they share your interest in femdom.