Summarize:

You may want to try several poses to find the most flattering one. If you have a timer, and a series option, you can set your camera to take several pictures at a time, which gives you time to pose or smile. You may look more together if you're not worried about operating the camera and posing. Give yourself more than enough time with the timer so you don't have to run back and forth too quickly. If you love the timer method, invest in a remote. You should try as many angles as possible to see which one is the most flattering and makes you look your best. Avoid taking photos from below because you'll look shorter or like you have a double-chin. If the camera is slightly above you, you'll look taller and slimmer. Avoid taking photos head-on. This will make you look boxy. Take the photo from the left or right to make your photo more dynamic. Try ten or twenty different angles. Have fun until you find your most flattering angle. Remember that one hairstyle can look great in one angle, while another would not look as nice in the same set-up. Try taking pictures in front of the mirror. This will add a new and fun perspective to your photo shoot. The camera will show up in the photo for a fun effect. Keep going until you get the perfect shot. Unless you have a Polaroid or film camera, you have nothing to lose. Try as many outfits or hairstyles as you want until you look just right. You can try a variety of backgrounds that make you stand out, whether you're at home or outside. If you found the perfect location, try taking pictures in the same place during different times of the day to see how the lighting affects your look. Show a friend or family member your picture before uploading it to the Internet to get a second opinion. You may think you look perfect, but an honest opinion could help you improve your next photo.
Set up your camera. Experiment with different angles. Take as many pictures as possible. Ask a friend for an opinion.