One of the things that often surprises me is how unprepared people are coming in to game shows. You can win your yearly salary but you walk in off the street with no preparation at all.
Obviously, I don't expect everyone to determine and memorize the information-theoretic optimal technique for extracting information from a word game or anything. But for Pete's sake, if you're going to be on the Wheel of Fortune, clock some time with one of the dozen or so computer or console implementations. If you're going to be on the Family Feud, take a moment to explain to funny Uncle Harry that saying the stupid-but-funny answer that popped into his head may cost him and four people who know where he lives a few thousand bucks. If you're going to play the old Concentration game, which was based on rebuses, spend a few hours brushing up on common rebus symbols and patterns.
(That's another show that, were it on today, would probably be broken by someone on the Internet. There is probably less than meets the eye when it comes to what can be done on a rebus. Someone could probably analyze the show's run and work out which are the most common syllables they can use, what is phonetically difficult to represent with rebuses, etc.)
ISTR that the Wheel of Fortune, for instance, edits out even more mistakes than you'll see on the show, which is plenty, according to one of the "behind the scenes" things. It isn't that hard, anyone can get it in 15 minutes or less, which suggests a lot of contestants come in with not even that much experience.
This is for many people the most bang-for-the-monetary-buck they will ever see in their lives. There are other things that will be more important, like having families, but monetarily, this is probably the most money-per-minute they will ever see. Put at least a bit of work into it!