Anal sex

So me and my boyfriend are going on 3 years. In the past year he has wanted me to try Anal so i have tried a few times and he loves it! For me, not so much.... it just hurts and i am so uncomfortable the entire time. I want to start doing it more for him, but i just don’t know how to make it good for me. Does anyone have any tips on how to make it better, and not hurt so bad😩. Please, i am so lost