No, no, no, do not paint small areas separately, almost completing them, or actually completing them, without first laying in larger areas of light and dark, or color. I was taught since I began courses in painting, that every portion of your painting surface should be colored. Never leave the bright white of canvas because color is relative; a color is seen differently depending on what color it is next to. So, I have departed from that rule here, and I did so with Portrait of Cat and other paintings as well. Why? Perhaps it is too much confidence, or arrogance. I have been painting for 40 years. I have grown to expect certain eventualities. I believe I can figure out what colors will do as I progress through a painting. All will come to fruition in the end because I have put in a great deal of time and effort learning and relearning as I have made my art over the decades. And it is gratifying to kiss some rules goodbye.