I've been working really hard to develop areas of value with my new favorite sketching pen - the thinline Sharpie. But what usually happens is everything goes to black before I want it to. I think I'll just continue until I get it to do what I want it to. Or until I get a thinner-line Sharpie. This drawing started out as a quick sketch of the shape of my cat's paws - he's polydactyl with two extra digits that makes his front paws look like mittens. Then I just went off stream-of-consciousness style to develop volumetric areas.