Nervous about anal

Help me out please ladies, because I’m nervous.

I’m not young or inexperienced. But the only time I’ve ever had anal, I was raped. Understandably, there’s a lot of mind-fuck surrounding anal, so I’ve avoided it for the last 20 years.

Next week is SO’s birthday, and I know he wants it, so I’m I’m committed to doing it.

But I’m fucking frightened.

Can you ladies coach me through anal sex please?

(Before anyone asks, he isn’t forcing me to do this, or making me feel bad for not wanting to previously. He’s been respectful. When he approached the subject months ago and told me he really liked anal sex, I told him, “I ain’t doing it. Not unless it’s your birthday.” And so now it actually IS his birthday, so I’ve consented.)