I’m the “new bizarre game I found on the Internet” guy in my group. There’s always some oddball game I want to introduce everyone to. Given my GM ADD, when I do get them to play a game, these are almost always one-shots, so I don’t expect anyone to actually sit down and memorize rules. Instead I make up a cheat-sheet that goes over character building and common action systems rules and types in easy to digest and reference chunks. For simple games, I can usually condense the entire game onto a sheet of 8.5 x 11 paper. For more complex ones, I usually just hit the high points and leave the less common details out.
These handouts help my players understand the game right out of the gate, and reduce the number of “How do I…” questions by a large margin. They also give me a quick reference sheet since the older I get the more spotty my memory is, but they also have another very helpful side effect. By going through the rules and deciding which parts are important enough to include and by condensing all the mechanics into an abbreviated form, I actually remember the rules better than just reading them. Just like writing reports (way) back in school, making use of the information and expressing it in your own way forces you to internalize it to a greater degree and requires you to understand it well enough to apply it. Presenting a game’s rules in boiled down format can also help make patterns and themes more obvious. While a game’s designer may have intended that certain subsystems mesh together in a certain way, fluff and samples tend to obscure the way mechanics interact. Pooling a list of systems together with nothing in between helps sort out synergies and strategies that may have otherwise gone overlooked.
Granted, some games are tough to write comprehensive one-page cheat-sheets for simply because of the bulk of the original rule systems, but even in these systems it’s often worth it to make a very generalized one or one for difficult or confusing subsystems. Even if you never give them to your players, excercising the rules will help cement them in your mind.