My moderators spend a long time putting people right because they haven't read the rules. It's very frustrating.
I had the idea that there could be a little quiz, which people have to answer all the questions correctly, before they are allowed to use certain features of the forum.
Such as they can't post an advert until they have done the selling quiz.
The questions and answers (and explanations of the answers) would be set up in the back end.
Not sure how it would be done, technically, but that's the plugin writer's task