Prep for anal?

Hi ladies. I’m planning to try anal sex for the first time but I want to take the proper steps to be sure I’m clean. I just don’t want any mistakes while this happens. Usually when I wash I stick my finger in slightly with my rag. I’m afraid once he’s in me there might be something I missed. For anyone that has tried it or actively has anal please help me out!! I don’t want to be embarrassed 😩