If you're going to be a KJ, sooner or later you will be asked to run a karaoke contest. No two KJ's will run a contest in exactly the same way. There are, however, certain components that every contest will have. These are what I'll be covering on this page.
The very first thing, and the very hardest thing, that you will need to do is to find at least two, (preferably three), fair and competent judges. You might think that this should be the responsibility of the establishment which is putting on the contest but I guarantee you that it is the KJ that takes the heat if there is some kind of judging absurdity. If I am asked to run a contest, I will insist on the right to screen the judges.
Next you will need a scoring system. I have been to and/or entered many karaoke contests. The scoring systems, in my opinion, are usually ridiculous. They may contain such categories as stage presence, appearance, and crowd response. Let's be realistic! This is karaoke, not Star Search. Karaoke is an entertainment for the average person to have fun with and maybe show off a little. Professional singers should go perform for money. This being said, the only two categories I will allow on the score sheets are difficulty of song and song performance. Normally with a scoring spread of 1-50 for difficulty and 1-100 for performance. You could use a scoring system of 1-5 and 1-10 but the higher numbers will help to reduce tied scores.
Most contests will have the categories of Best Male, Best Female, and Best Duet. Sometimes there is more than just first place for each category. These decisions, along with what prizes that are to be awarded, are the responsibility of whoever is putting on the contest. The size of the prizes and the amount of advertising will determine the turn out.
The fairest way I've found to determine the contestant line-up is to set a time deadline for registering and then writing all the names on separate papers, folding them, placing them in a box, and drawing them randomly. This will avoid any arguments that may arise with contestants who want to sing first, last, or at some certain place in between. It will speed things up some if you have the contestants write down the number of the song they wish to do when they register.