Professionals would only keep only between 1-10% of photos with them. Models don’t just walk on to set, take one photo, and leave. Change your angles and what you are doing. The more options would be available, the easier it would be in the selection process.
Elongate your neck, and tilt your chin just a bit. Do not slouch. Keep your shoulders back. If you are standing, turn slightly and rest your weight on your back leg. Don’t keep your legs together and shoulders straight. Lean slightly toward the camera and angle your face and/or body. Ensure the lens is above you, if the photographer is shorter than you, move to an area where they can stand on something or you can get below the lens. Head shots can also be more pleasing if only one ear is showing.
Laugh and smile. Keep your tongue behind your teeth. Look slightly above the lens. Try looking away from the camera and a few facial expressions. Candid shots are engaging and more interesting than the traditional forced smile, which can create a forced look and squinty eyes.
Your eyes are the key. Holding a pose and keeping your eyes engaged is difficult. So close your eyes and then open them. Look away, and then look back to the camera. Do something unexpected. Talk to the photographer. Face your eyes towards the light source: catchlights create sparkle and immediately add life to your eyes. If you are outdoors, stand in the shade, and face the light. If you are indoors, face a window at an angle.
Wear a color that flatters you. Don’t wear clothes that have crazy patterns, it will distract from your photo. Stay away from striped/checkered shirts. Also make sure your clothes aren’t wrinkled or bunching up, it can add weight if clothes are too baggy.
Make sure your hair is brushed; you don’t want a stray hair distracting. If you have a blemish, cover it. If your eyes look red, use eye drops. Brush your teeth, use a teeth whitener.
Don’t take photos in direct sunlight or with a direct flash. This is unflattering and will cause harsh shadows. Move into the shade, or make sure the flash is bouncing off the wall. Soft light smoothes wrinkles.
You don’t want your background to distract. Take a look at what is behind you. You don’t want a tree growing out of your head. Aim for a clean and simple background that contrasts with you. If you have black hair, stay away from a dark black background. If you are wearing all white, you may not want to stand directly in front of an all white background.
Try not to appear too tense and rigid. Dance around a little and shake out your body.
Do something with your hands and use props. Below is a recent maternity photo of me, with a prop. I was getting tired and pictures were falling flat. Once you grab a prop, the shots got better.