So you signed up to be in a KGS tournament. What do you do? First, most important, read the requirements and rules sections below. Tournament games are different from normal games, and it is important that you know what to expect!
Next, look up the tournament schedule. All KGS tournaments are listed at the KGS tournaments page. Find your tournament. A list of all players signed up will be there. Also, shortly before the first round is due to start, the schedule will appear. When it shows up, check the schedule to see when your game is. Make sure that you are logged on to KGS at least two minutes early! In most tournaments, if you aren't there two minutes early, then you will be dropped from the round, or perhaps dropped from the entire tournament.
Once you get to KGS, just wait. As long as you have a new enough client, you will be notified when your game has been set up by the tournament director. Often this game will be in a special tournament-only room on KGS; the notice will tell you which room the game is in. Once you get this notification, you have one minute to join the game. Go to the room with your game by choosing "Room List" under the "Rooms" menu option, then clicking on the room name. Find your game, click on it to join it, then wait! When the game actually starts, you will get a second notice letting you know and your clock will start counting down. Start playing!
Before playing in a KGS tournament, you must have the latest version of the client. If you are using a web browser (Internet Explorer, etc.) to play, then you will have the latest version, but if at all possible it is recommended that you use the downloaded version of the client instead. The downloaded version of the client will be much more realible and less likely to crash when you are playing your game!
To check your client version, start it up; the version is printed in the lower left corner, under the "Configure" button. Go to the download page and see what the latest version available is. If you don't have the latest version, please download it before starting the tournament!