The flash on your camera is very limiting. It tends to make flat light, with harsh shadows behind your subject, and often creates red eyes in your subjects. Avoid those problems by getting a flash that allows you to move it off-camera. For digital SLRs, this means using an accessory flash with an extension cable (though some newer cameras do have wireless flash capabilities).

For small, compact, and point-and-shoot cameras, you can also use this technique by purchasing one of the little flashes designed to be triggered by your on-camera flash. (These can also be used with a digital SLR, but for more versatile light, the accessory flash with cord works better.)

You do not have to get the flash far off-camera for it to work well. Hold the flash with one hand off to the side and point it at your subject. This provides nice directional light with far more attractive shadows than the on-camera flash will do. You can also point the flash at a white wall or a reflector to create a very nice, softer sidelight.