I worked for several weeks on the back of one of my water color journals, trying to salvage an image that was there. It was a face (of course!) but I'd used colored pencil and basically she'd acquired a skin disease.
So finally one night I took out a massive white Sharpie paint pen and scribbled over everything, so I could start over. This is the face that emerged. I used Inktense pencils, more white Sharpie paint and some pen for the eyes. MUCH better.