Add a reflector, and you’re golden.
By the way, this is how I’ve been taking photos of my work. I haven’t got around to making a light box, or buying lights, so I wait for a sunny day and break out the white paper. I use photoshop for editing. Levels, contrast, colour correction, cropping, and sometimes to fix the background (for my larger pieces I had to use 3 sheets of paper, and I edit out the joints).