A typical commercial is about 30 seconds, during which time you need to present visual and audio information engaging enough to entice an audience into buying a product. This requires good writing and a skilled director, which is why many film schools suggest filming a commercial as an assignment. Learn how to make a good commercial for school that will showcase not only the product you choose to highlight but your skills as a director as well.
Write an audio/video script. The script should be two columns. One column will be for video, describing everything your audience sees, and the other will be for audio, describing what your audience hears. Having a script not only saves time by letting you know exactly what you will be shooting for your commercial, but also by allowing you to determine what sound effects, locations and actors you'll need.
Focus the message of your commercial. Use visual effects to highlight the subject of your product. Pay attention to lighting and details. If the commercial is about food, make sure you capture the sound of the food sizzling. If you're making a commercial about a cold drink, choose a setting that would put the audience in a thirsty frame of mind. The sun beating down on people sweating in the sun with a bottle of the soft drink sitting in a nearby bed of ice is a good idea. The juxtaposition of the two opposing elements brings the message to the forefront.
Grab the audience's attention up front with an image or tag line that will make them pay attention, inform them about the subject of the commercial and engage them with a mini story. Humor in a commercial is always a good way to keep an audience around.
Keep the budget low. Odds are your school will want to see what you can come up with creatively when you have a small budget. Keep locations down to one or two, use as few actors as you can and shoot during the day because it saves money on lighting. Shoot your commercial with the best quality camera you can find. You can use a hand-held digital if you don't have access to a professional big-budget movie camera, but be sure to attach the camera to something solid with wheels. This allows you to move the camera without creating shaky images.