Trying doesn't work. Relax and let go.
Have you played with seeing the energy between your fingertips? Another one is to get some fresh apple seeds and place them on white paper. See if you can see that aura and check out plants as well.
Also the reason you might only see one side is that you're too close to the person and the background isn't an even light. Try a dark background if you've been using a light one and a light background if you're using a dark one. When outside try seeing it early in the morning or near sunset. Some folks have better ease seeing in that light.
Alex
