Toastmasters is a great organization, and you can learn a lot, and get a lot out of it, just by following the standard educational program, at least if you find yourself a good club that fits your style and gives you plenty of chances to speak.
But if you want to go farther -- and especially if you want to win contests -- there are a lot of things you need to know which aren't written anywhere in Toastmasters literature. The only way to learn these secrets is word of mouth, from other Toastmasters.
Enough secrecy! Here's a collection of Toastmasters Unwritten Rules. If you have others you think I should add, please let me know.
In this region, there's an unspoken assumption that you're supposed to address your audience -- "Mister/Madam Toastmaster, fellow club members, and honored guests" or something similar -- at the beginning of your speech or very shortly thereafter. We even do it in Table Topics. Why? Nothing in the Basic Manual ever mentions this, and you almost never hear a good speaker outside of Toastmasters beginning a speech this way.
Certainly it's usually a bad idea to offend your audience. But lots of clubs do allow speeches on political or otherwise sensitive topics. This "rule" varies by club; don't assume all clubs are the same.
What about contests? I've actually heard of contests where a contestant was protested because of including one of these verboten subject areas in his speech. But this is not in the rules anywhere; in theory, you're allowed to talk about anything you like, and it's up to you to avoid offending audience members. (One of our club members gave an excellent humorous speech about religion in a recent contest, presenting funny situations from herself and other members of her church. She did a great job, and no one was offended.)
At a humorous contest a couple years ago, a contestant made a big deal about how every Toastmaster knows that you're not supposed to call the thing at the front of the room a "podium", it's a "lectern". Apparently they make a big deal of that in his club. First I'd heard of it -- both my clubs call it a podium. If you look it up, both terms are correct, but be aware if you enter a contest or speak at another club that some people feel, bizarrely, very strongly about this and will wrongly downgrade you if you use the word "podium".
A letter in Toastmaster magazine recently said "Toastmasters literature emphasizes that evaluators and audiences should focus on the delivery of a speech, not the content." On the other hand, the judging sheet for contest speeches reserves 50% of points for content, and only 30% for delivery (the remaining 20% is for language). Which is true? Depends on the evaluator/judge. Me, I think they're both important.
The rules for the International contest say you can speak about any topic, and you can certainly enter your area contest with any good speech you choose to enter. Don't expect to get very far with that, though. It can be done -- like Anurag Shukla's very funny and not at all inspirational District-winning speech -- but you'd better be truly exceptional if you're going to buck that trend.
Every contest I've been to has defined a "speaking area" -- usually a rectangular area from right in front of the audience front row back to the wall behind the speaker. No more is said about this "speaking area" or why it has been defined. Speakers, and judges, naturally assume that it is an area beyond which speakers are not supposed to venture. A speaker who does cross the bounds of the speaking area will presumably be disqualified, or marked down by the judges, or (I especially like this one) treated as though any part of his speech that took place outside the boundaries did not happen and was not visible or audible to the audience.
Guess what? The "speaking area" is a fiction, and nothing in the rules even says that a speaker is supposed to stay inside it. Here's what one highly successful competitor and long-time Toastmaster thinks it means:
The Speaking Area, as I undderstand it, is an optimal area for speaking; within that area the lighting will be fine, the technology will work (e.g. range of the wireless mike), and the audience will have clear sightlines, etc. You may venture outside that area, but you take your chances when you do so (e.g. risk of going into a darkly lit spot).
So should you feel free to ignore the speaking area? No way. Because most judges still think that it's part of the rules that the competitor has to stay inside it. Ignore it at your own risk.
Some clubs apparently encourage formal attire, and consider that an important part of Toastmasters. I've never actually been to a club like that, but I see it mentioned in places like Toastmaster magazine (probably east-coast people are a lot more formal than we are in California).
It may be important for speech contests, though: even people from clubs which dress informally may have ideas about appropriate attire for contests, and generally you'll see more formal dress as you progress up the ladder.
Apparently some regions even have additional unwritten rules, like "women must wear dresses" (and will be downgraded if they're not).
The written rules say that when applying for any of the Advanced Communicator awards, you can't use a manual you've completed before.
But obviously, this resets at some point, otherwise, when you'd completed all the manuals, you'd be done forever (except for infinite CC awards from then on).
Most people assume that it resets when you get AC-Gold/DTM, but other people insist they've been told by TMI that it only resets after you've completed ALL the manuals. In other words, you have to do every manual in the series, then you can go back to the ones that are useful to you.
No one seems to know whether this is currently enforced.
Apparently after your first DTM, you can get subsequent ones by repeating AL-Silver and AL-Gold. No need to repeat CC and AL-Bronze. Seriously! Never mind that the written rules say that one of the requirements for AC-S is AC-B -- apparently that just means that you needed to get one at some point in your life, and after that you can repeat any award except DTM in any order.