I know what your thinking there are no lines on that drawing. Well, to be honest with  you, when i saw my drawing with looked tacky, the black using so much space when it can be used for color instead.  I decide to make a test and see if it would look good. I started with nose  because  I saw that part as HIDEOUS and it did look good, i did lips mouth and eyebrows and , indeed it look better. how did mostly is  using the same color as color standing next  the line that i was erasing, i would isolate the line meaning that only that line would change color. Some times i just had  to use a large brush and remove the line manually. I also learned how to do the gradient myself