To build a fog machine, use either dry ice and a fan or a glycerin and water mix and heat. With dry ice, fill a five gallon bucket nearly full with hot water. Using gloves and tongs, carefully place one piece of dry ice into the water. Place a fan behind the bucket in the direction the fog needs to travel. Add hot water and additional pieces of dry ice as needed.
For a glycerin and water fog machine, mix one part glycerin to three parts of distilled water. Cut off the top of a 2-liter bottle and tape the cut end onto the center of a pie plate so it resembles a cone. Take an empty metal coffee or soup can and punch several small holes in the base of the unopened side of the can. Place a large candle with multiple wicks into the can and light it.
Arrange the pie plate over the open side of the can and add a teaspoon of the glycerin and water mixture. The heat from the candle causes the mixture to produce a dense cloud of fog. Place a standing fan on a light setting above the can, but low enough to direct the fog. A teaspoon of mixture is enough to fill a large room, but add more mixture as needed.