This is a very simple, beginner method, but with enough practice things will get clearer, and you can see more at once.
1. Facing a white or black wall in good lighting, put you arm straight out in front of you with your palm facing the wall.
2. Spread your fingers, and look between them at the spaces. Keep your eyes relaxed and generally unfocused.
3. You should see an energy field around your fingers developing in your peripheral vision. It usually starts out clear, and with practice you see colour.
4. It may help to move your hand slightly. I find if I do this that the aura leaves a ‘trace’ for a few seconds, allowing me to see it clearly. Sending energy out of your hand or visualizing it becoming stronger also helps.
5. Keep practicing. In time you can see different layers and colours, on yourself as well as other people, coming from the entire body.