1. Open up your sketch or a downloaded sketch (whatever you want)



2. Create a new layer beneath your sketch layer and name it face(or skin) color



3. Roughly color the skin parts (I used #eed4bd)



4. Create a new layer beneath your sketch layer(and above your skin layer) and name it hair color



5. Roughly color the hair parts (I used #917352) (Repeat this for eyes, clothing, whatever you want/need)



6. Now create a new layer above the face/skin color layer and do the same for the hair



7. Now color in the shade parts of the skin (I used #b99e82), the hair (I used #53402b), and repeat this for eyes or whatever you want/need



8. Repeat steps 6 and 7, only use a lighter shade color then the first time





9. I forgot to do the lips and eyes, so repeat steps 6 and 7





10. Select the first shade layer (I am showing the skin in this tutorial) and apply a 3.0 Gaussian Blur to it




11. Do the same for the second shade layer



This should give you the following effect:



12. Repeat steps 10 and 11 for the hair, eyes, lips, etc



13. My hair shade wasn't dark enough so I duplicated the shade layer a few times to get a darker shade



14. Adding highlights/some more light. Create a new layer above the sin layers you have so far, name it face/skin highlights or something like that



15. Roughly color in the highlights with white.



16. Blur this highlights layer to something that looks natural and drop the opacity (I dropped mine by about 60 percent)



17. Repeat steps 14, 15 and 16 for the lips , hair , etc (whatever you want)



18. Create a layer called final edits, or something like that



19. In this layer make some final edits, I added some more darkness to the eyes, brushed up the hair on a few parts and added a reflection in the eyes



20. Duplicate the sketch layer, blur the copy by 0.5 pixels and drop the opacity a bit (mine dropped roughly 50 percent)



This should leave you with the following result:




My final product (a lot more steps are involved in this image):