TL;DR
Great video requires great lighting. To achieve a professional look, avoid standard incandescent bulbs, utilize a proper 3-point lighting setup (key, fill, and back light), and always manually white balance your camera to prevent harsh yellow or blue color tints.
Throughout the years, we’ve had quite a few great basic audio tips posts. Many people say that without great audio, you can’t have a great video. But, being visual, I contend that the video picture is just as important as audio. And what’s the one most important element to making a great video picture? Lighting!
When you’re filming video, whether it’s on your built-in iSight camera or through an external camera, your lighting will make a big impact on the quality of your final video.
Here are a few simple tips for making sure your videos have great lighting.
Use good lighting sources
There are lots of sources of light available to us, and if you don’t have enough light your video may look grainy or out of focus. The free option is sunlight, of course; shoot outside or in front of a window. The cheap option is to use simple clip lights you can find at Home Depot or any photography shop. More 
professional set-ups use full lighting kits that may include reflectors, and soft boxes, etc.
If you choose to use a non-natural light source, try to use either halogen bulbs
or fluorescent lights. Incandescent bulbs tend to create yellow light, particularly if they are old or on dimmers, and they often don’t provide the best lighting for cameras. Halogen and fluorescent lights are provide a better light for video.
Place your lights appropriately
Whatever the light source, you want to place your lights to illuminate your subject, fill in any shadows, and create some depth and interest. (Unless you’re going for the Halloween goblin look, it’s best not to direct a light upward from directly under your chin, for example.)
Make sure you have sufficient light to illuminate your subject. Diffused light works better than direct lighting (point the light at a wall rather than directly at your face).
Avoid too much back light. This creates a situation where your subject will simply appear as a shadowy silhouette.
Here’s a great video by VideoMaker on how to use a 3-point lighting technique – which essentially has you place a Key light, a Filler light and a Back light to balance your light and shadows.
