1. Built-in vs. external flash units
A built-in flash unit is generally quite small because it shares its power source with the other parts of your camera. As a result, you should stand no further than 2-3 meters away from your subject if you intended to use your camera’s built-in flash. If such a close distance between you and your subject isn’t possible (perhaps you’re at a rock concert), turn your flash off and turn up the ISO setting. External flash units are of course available, but can be quite big because they have their own power sources.
2. Slow Sync Flash
Because built-in flash units simply generate more light as opposed to directing it, any unique rays of light in the composition will be lost. To avoid this phenomenon, try Slow Sync Flash. With this application, you choose a slower shutter speed and ignite the flash while the shutter is open.
3. Diffuse or Direct Your Flash DIY style
While fixed-flash units do not offer wide range, certain Do It Yourself approaches can diffuse or direct the light to your liking. You can put a piece of semi-opaque adhesive tape over the flash to diffuse the light or put a white card in front of the flash to bounce it up or sideways to direct the light. Note that your camera will not know that you’re adjusting the light so you may need to compensate and increase the exposure by a notch or two.
4. Fill-in Flash
The purpose of a flash is to add more light to an image, not to be the sole light for that image. So use your flash when photographing a subject with harsh downward light or strong backlighting (like this picture of a kitten), not to illuminate a dark space. For areas with heavy shadows use a fill-in flash, although beware that the entire background (not just the shadows) will appear significantly brighter.