Tripods have a variety of uses for photographers of all levels. When photographing objects in low light, such as a shot at night or in an area of the house that does not receive a lot of natural light, a tripod is a necessity for keeping the camera still while the shutter is open. For any shutter speed slower than 1/30 of a second, a tripod is vital. And sometimes you need a tripod to set up a shot using the camera's remote or timer features. Homemade tripods can come in useful for such situations.
The easiest way to steady the camera is to place it on a tabletop or counter, this will give you a solid, unmoving base so you can keep the shutter open for longer periods of time. If you need something mobile, you can use an ironing board or a saw horse from the shop or garage to steady the camera. Another option is an inexpensive artist's easel that you can use, placing the camera where you would place the painting. A broomstick or mop handle unscrewed from the base can be modified to serve as a monopod. This will not give you the same steadiness as a the above options, and is not a good method for night shots, but it is highly mobile, easy to carry and work with outdoors (if you are taking nature shots, for example) and with care can provide a steady base for shots that are close to the 1/30 of a second range.
When you are shooting in low light, or need a steady base, is to pick up a cable release. This is a wire that screws directly into your camera with a small plunger on the other end. Depressing the plunger activates the shutter and takes the picture. A cable release can be a big help because there is no shake from manually depressing the shutter button on the camera. Adding more light, or moving your subject to an area with better illumination can eliminate the need for a tripod completely, giving you more freedom as to how you compose your picture. It will also give you more options with you aperture settings. In low light, you need to open your aperture all the way to allow the maximum light to reach the film or digital sensor. This reduces your depth of field radically, and only the objects you are focusing on directly will be in focus in your picture; objects in front of or behind that spot will be blurry.