If you ask any professional camera operator how they started training and practicing to become better shooters, one of the first pieces of advice they will give you is to use a tripod. Tripods will help you master a variety of shots including pans, zooms and tilts. A tripod will keep your shots steady and looking professional. They are also very affordable and should make an immediate difference in the quality of your video.
Another subject that all good camera operators understand is lighting. Because light is basically what the camera is recording, it is important to understand how it works and interacts with the camera. For training, try renting a light kit or borrowing one from someone you know to experiment with lights indoors. You should notice, that when used properly, lights can enhance your shots and prevent you from recording washed-out or grainy video. For outside shooting, take the time to understand how your camera reacts to clear skies, cloudy days and the night.
Unless you are shooting a silent film, you should also understand how audio works. Most camcorders do not have the best built-in microphones and for a lot of amateur video, audio is usually one part of the film that struggles. To make the next step towards shooting professional video, take the time to learn how different microphones work, and even buy an external microphone for you camera. Training to master audio skills will greatly alter how professional your video comes across.
If there is one phrase and concept you learn that will make your video look more professional, it is the rule of thirds. The rule of thirds is a framing technique that breaks a shot into a three-by-three grid. Each intersecting line in the grid represents a spot on screen that our eyes naturally gravitate towards. By training to place important elements at these intersecting lines, you will have better-looking video in no time.
Even though the fact that your camcorder can zoom in extremely far sounds like a cool idea, it actually creates poor quality video. To shoot more professional looking footage, only use the camera's optical zoom. The difference between digital and optical zoom is that digital zoom is enlarging pixels, whereas optical zoom is actually using the physical qualities of the camera lens to enlarge the image.
One other way that you can train to shoot professional video is by shooting as much as possible while practicing the above techniques. If you train your body and mind to always think in a filmmaking mindset, these professional techniques will become second nature, and your skills as a professional videographer will increase dramatically.