For the record, we are playing the version of the show that originally aired from 1973 to 1982 under the names "Match Game," "Match Game '73" ('74, '75, etc.), and "Match Game PM." The specific rules are a hybrid of the "daytime" and "nighttime" games.
Chris Lambert's Match Game Homepage has a good overview of the version we will play, although we do not have the Match the Audience bonus round.
There are two contestants (chosen randomly from the audience) and six Panelists. We will play two rounds with two questions per round (one per contestant). In each question, we read a fill-in-the-blank statement, such as:
"Admiral Jones said, 'Captain Kirk has the biggest _____ in Starfleet!'"
Panelists then write how they would fill in the blank on cards. When they are finished, we ask the contestant to give the answer that s/he thinks will match the most panelists. Contestants get one point per panelist matched. Panelists who match in round 1 do not play in round 2.
Double entendres are encouraged. Round 1 questions are generally vaguer and more difficult to match. Because we do have children about, I ask people to keep the show to PG-13 if they can.
If after two rounds the contestants are tied, we wipe the scores and play a tie-breaker round using the same rules. If the score is still tied after that, we go to sudden death. In this, we ask the contestants a simple fill-in-the-blank, like "Star _____" and they write down their response. We then go to the panel one at a time and ask their response. When the panelist response matches a contestant, that contestant wins. If it matches both contestants, or if no panelists match the contestants, we repeat sudden death. (I've never gone past a second sudden-death round.)
As I mentioned, we will not play the Match the Audience bonus game, because conducting the necessary audience surveys is too difficult. We could play the Bonus Match, in which the contestant picks one panelist, we do a simple match (like the tie breaker), and the contestant gets one chance to match that panelist -- if s/he does, s/he wins the prize. However, at least at Westercon, we'll not do the Bonus Match. Instead, each panelist will hold up an envelope, and the contestant who won the main game will pick that one panelist. The panelist will open the envelope and the contestant will win that prize. (Obviously, you can only pick from among those panelists who still have a prize left.)
We will take two new contestants per game (to maximize number of contestants) like Match Game PM, but will only play two rounds per game like the daytime version.
We plan to play six games in two hours. I think this is reasonable given that we played five in 90 minutes at BayCon, and we rushed game 5 because we were running out of time.