Light the scene well. The camera functions the same way as an eye, making it crucial to consider how light reflects off of your subject. You can also use light to suggest a time of day or mood. If your scene is poorly lit, even the best cinematographer has limited options.
Set up the shot. Don't just think about what you want the camera to capture; think about where you want the audience to see the shot from. Experiment with moving the camera to different locations and strange vantage points. Try shooting from down low or up high. Make sure that your perspective suits the mood you're trying to evoke.
Experiment with the duration of the scene. Keeping a camera running long after the scene is finished is a great way to capture bits of film that you might otherwise miss. Start rolling before the scene starts and leave it on after it finishes. You can always edit the scenes in post-production.
Master your camera. Looking down at your camera's settings might give you a headache, but functions such as aperture and focus will help you improve your camera work. For example, aperture controls the amount of light entering your lens. It is measured in f-stops and a high f-stop number will decrease the amount of light entering the camera, focusing the lens on objects in the foreground.
Take a film-making class. If you're serious about being a filmmaker, a class will help you learn the basics of cinematography and give you a chance to experiment with different cameras and styles. If your interest lies exclusively in cinematography, try to find a class that caters to this field.
Purchase a better camera. Although, a great cinematographer can make do with a poor quality camera, purchasing a newer, more expensive model will greatly improve the quality of the picture. Save up your money and try to purchase a high-definition camera that will improve the quality of your shots.