In time-lapse photography, the camera must be in the same exact spot for the duration of your project. The slightest movement of the camera will show up in the finished movie and even be exaggerated.
A tripod also allows you to plan the composition of your shots more carefully.
When thinking about the composition of your shot, consider the camera angle. Most shots are recorded at eye level. However, a high or low angle might be right for your project. Also look at the background in your shot. Does it add to the picture or is it distracting?
Experiment with the zoom of the lens. If you are recording something like cookies disappearing from a plate, a tight shot will be best. To document the changing seasons, use a wider shot.
Observe the lighting in your shot. Generally, you want the light to be coming from behind you and a little off-center so that it shines on the action. If you are working indoors make sure there is enough light. Depending on your set, you may need to use more.