Trying new things

Okay so my boyfriend is waaaay more experienced with sex as far as trying different things. I’m 20 turning 21 he’s 21 turning 22. He wants to try anal with me and eating my ass. Now he’s experienced with that but i for one have never wanted to do it. But i know it’ll please him. So how do you prepare yourself for something like that ? Or any tips to get used to it or any advice at all ? He’s not forcing me I’m 100% consenting to it and wanting to try it