1. Copy the character layer.
2. Then on the top layer go up to effects and use pencil sketch.
EXAMPLE
3. Now create another copy of your original and use black and white.
EXAMPLE
4. Then use brightness/contrast to lighten up the image even more.
5. Now with the pencil sketch image on top of the lightened black and white image select the pencil sketch image. Now go to the properties button of your layer box and change the mode to multiply and click OK.
EXAMPLE
6. Now move you original on top and use the magic wand or the eraser to cut out the colors you want to change to white.
7. Flatten the layers when you got everything you want white and you're done.
