Trigger warning

I have a question.. so I was sexually abused when I was younger both vaginally and anally. But... I’m married and happy now.. and I really want to fulfill my husbands fantasy of anal. And I’m curious about it too. But also super nervous about being triggered as that was the worst part for me. How do I go about preparation? And being comfortable doing it. He knows the word no and stop we’ve had to stop having regular sex before. So that’s not an issue. I want to ease into it. Is there anything I can do to start the process? Thank you in advance. My sex life has been complicated due to the past. But I’m lucky enough to have a very patient and supportive husband.