Choose the camera you want to use for the time-lapse shoot. Whether shooting a series of photos or a video of the sun across the sky, the concept remains the same. In fact, a video is actually composed of a series of photos that change very slowly per shot and provides the illusion of movement when they are shown in the right sequence of action.
Most digital video cameras have an "Interval Recording" function, which allows you to instruct the camera how long you want it to record and how long you want it to stop recording in between certain intervals. For instance, a still or video camera can shoot one photo or video every one minute, 10 minutes or 30 minutes for a total time period of one hour, six hours, 12 hours, 24 hours or even longer.
Set up your shot of the sky in your chosen location. Secure a location where you can put your camera on a tripod without the risk of accidentally moving it from its original position. Even a very small change of location becomes a big problem with a time-lapse effect, which may require you to repeat the process all over again.
Set the "Interval Recording" function of the camera. You can actually do this manually if your camera doesn't have this function, but doing so provides much risk of you accidentally moving the camera out of its original position. If you're using a video camera, you may continuously record to get enough footage for the time lapse. However, take note of the length of time you can actually record before you run out of tape, memory card or camera battery. Take all these things into consideration, especially if your camera doesn't have an "Interval Recording" function.
Carefully plan how many times in a given time period you want the camera to shoot the sun across the sky. The longer the time-lapse you want, the longer the time you need to shoot the sun and the sky. Technically, if you want to shoot from sunrise to sunset, you have to be able set up and shoot right before the sunrise until the sun finally sets.
Assemble or compile the video or photos in the computer. Open the photo or video elements in a video editing program and play them according to the sequence they are shot.
Export the project into a movie so you can readily see the tracking of the sun across the sky. Although the process of exporting varies from one program to another, the "Export" function is typically found under the "File" menu. You may export the video in any compatible movie file format, such as MOV, MP4, 3GP, AVI and WMV.