anal tips!!! please

so my boyfriend and I are finally getting a little more “adventurous” in bed. I brought up the idea of anal. he started teasing my ass with his fingers and dick and suddenly i’m nervous. I still want to try it but any tips for first timers?? I know we need lots of lube but is there anything I should do prior to the dick appointment? anything I can do to make it more pleasurable for me and clean?? idk I always thought it’d be messy idk but please lmk in the comments!!