First, put some thought into the background. It shouldn't distract from the subject. A plain wall, dark green foliage—anything that's simple (without strong lines or patterns) works well. There's nothing worse than a line, pole or branch going through or growing out of the subject's head. Then, make sure the background is not brighter than the subject. The human eye is drawn to the brightest parts of an image and a bright background can cause an exposure problem, too.

If you photograph someone against a bright background, you may well end up with a silhouette. That's because the brightness can cause the camera to underexpose the subject, making her look dark. You could pop up your Nikon D-SLR's built-in flash or turn on the flash in your COOLPIX camera to add light to your subject's face, but you'd still have that bright background.

Every Nikon D-SLR and COOLPIX has exposure compensation, so you could overexpose by one or two f/stops or shutter speeds as well. If these methods don't work, then try a different background, preferably something darker than the subject.

Keep in mind that the picture is about your subject. Don't shoot the whole area around the person. Get closer by physically moving in or by  using a NIKKOR  telephoto or telephoto zoom lens. Isolate your subject against that simple background you found. People's heads are vertical, so shoot them that way. Horizontal portraits can look uncomfortable.

Next, consider how the subject is dressed. Solid colors and black tend to work well in portraits, mainly because they're not distracting (remember that bit from backgrounds, right?). Bright patterns scream out, "Look at me, don't look at the subject!"

Finally, unless you shoot mug shots for the local police department, don't photograph your subject head-on. Have her turn her body a little, maybe 45 degrees away from you, and then rotate her head back to face you. (Tell her, "Don't move your shoulders, just turn your head to me.") It's a nicer, more flattering pose and helps slim people down.