Veralynne has very good advice. Slow and slow and slow, work up to it. If you enjoy anal sex, and you enjoy rough sex, rough anal sex will be enjoyable with sufficient preparation.

Work on stretching for a while before hand- toys if you have them, and slower more gentle sex. The day of, lots n lots of foreplay, and then as Veralynne said, make sure you are good and hot. And lots of lube!

The hardest anal sex, for me, is if we have vaginal sex after some anal foreplay, I'm begging for it before long, and eager for more.

Good Luck!