Anal advise and stories

Okay me and my boyfriend have recently been thinking about trying anal out but I've been trying to avoid it because I'm sort of worried about how it'll be. I want to try it too but I'm scared it'll get messy? Whoever knows, do you recommend me pooping before? I've heard stories about guys getting poo on their bits and I feel like that's so embarrassing I don't want that to happen. Has anyone got any advise? Or share your stories about the first time you tried anal.
Thanks