This is my drawing. I used Arches cold press watercolor paper 140 lb, stretched on my board and worked from a picture. I painted the background with some India ink

This is the first layer. I used only Yellow ocher (Da Vinci).I used a paint shop pro CMYK split channel image as a guide. I will soon post a tutorial about this on my painting blog

This is the second layer, I used a Pinkish warm red (Alizarin crimson, Da Vinci) and some more orange-red (Permanent red light) on places I wanted a more orange color. Because I am painting with just one color, I can really focus on tone and edge quality.

On the third layers I used mostly a warm blue on most of the shades of the face (Ultramarine Rembrandt). I try to have a very light touch with the blue as it will easily over-power the rest of the colors on the skin.

I am adjusting the colors by adding some new ones and scrubbing with a stiff brush and lots of water where I want to remove color or soften some edges.

Here, I start to work on the background, I didn't have a precise idea of what I would do in the background when I started, so I am experimenting, playing with some idea. Because I added white acrylic paint on top of the India ink, any watercolor I am applying next could be easily removed with a wet fabric.

The finished painting, I decided to add some patterns in the background, reminiscent of a Klimt style painting.