Nothing ruins a good video like too much camera shake. And the best way to prevent shaking in your moving shots is with some kind of camera stabilizer.
Two of the most common types of camera stabilizers that are used in the film industry are the Steadicam and the Fig Rig. These systems are very effective. But most amateur film makers don't always have access to this kind of professional equipment. Fortunately, you can use the operating principles behind these systems to make simple DIY camera stabilizers out of materials that you have lying around. Here are two basic examples.
Step 1: Background: How a Steadicam Stabilizer Works
Following this principle, you can improve the stability of your camera by simply adding weight to it. The amount of weight that you need to add is proportional to the weight of the camera. As a general rule your weight should be at least as heavy as your camera in order to be effective.
The Steadicam is designed to accommodate large professional video cameras. As a result, the system has heavy counterweights and requires a substantial support system. But when working with small point-and-shoot cameras, the system can be greatly simplified. The support vest, the iso-elastic arm and the gimbal can be removed and the stabilizing weights can be attached directly to the camera. This is the basic design of handheld camera stabilizers like the Merlin stabilizer.