You explained it much better than I, Mary. :) In the image I did above, I clicked once to paint with it, then duplicated it two times, so I had three layers. In this particular one, I changed the bottom layer to black, set the middle layer to either Color Burn or Soft Light, depending on which brush I was working with, then the top layer was set to white or another light color, with layer style set to either Color Burn or Soft Light or I think there was even one more style that I can't think of right now. Overlay works well a lot of times too, and dont be afraid to vary the opacity of each blending effect. Sometimes an overlay can look too harsh, but if you bump it down to about 60%, it has a much nicer look. Just keep changing the layer effects, add more layers with different effects or colors, you might be surprised. :D