For this drawing I clicked the "reserve transparency" button on the "layer menu" to do the gradients. Each layer is a different color, like you would do solid coloring but each color on a separate layer. In addition, you can select individual pieces with the "magic wand" tool with the reserve transparency still on or use the "select rectangle or oval" tool to do your gradients. which is handy if your selected area was made with the anti-alias or blending, whereas using the magic wand around blended/anti-alias areas to do gradients would leave a line around the selected area, you don't want that. That was all very long winded, I hope you understood and I hope it helps. :D