In my art school days, I accumulated various supplies, and two of these items, Acrylic Fluid Matt Medium and Acrylic Fluid Gloss Medium, struck me as an interesting start. I have 2 oz. bottles of each, made by Windsor & Newton which were included in my art school supply kit. I also had a mysterious liquid in a baby jar that looked like watered down white acrylic paint.
First I applied the runny paint to one page to test my theory. It was exactly what I had guessed. It just soaked into the page and made it damp. On another page, I applied Acrylic Fluid Glossy Medium with some white acrylic paint straight from the bottle and after it dried, I tried drawing on it with a mechanical led pencil, but it was too slick for my liking. On another page where I applied Acrylic Fluid Matt Medium with white acrylic paint and after it had dried, the pencil glided smoothly and eventually a doodle formed in the shape of a mermaid. I was also able to erase my stray marks with ease.
After erasing some stray marks (I wasn't too concerned since it's just my altered book after all!), I used a black Bic pen to trace the main shape. I used a watercolor pencil inside the mermaid after wetting the page slightly. The water stayed on the surface of the page, allowing the color to be blended without soaking into the page. Then I continued drawing some doodles with the watercolor pencil in the background. After it dried overnight, I used my Koi watercolor pallet paints to darken the area around the mermaid, then after a few minutes, used Bic pen to doodle in more swirls. I outlined the mermaid with a white Gelly Roll pen but wasn't pleased at the opacity of the pen. Using a thin brush and white acrylic paint would have worked better.
I'm pretty pleased with how the Acrylic Matt Medium made the book page sturdy and prevented the paper from pilling (when the paper fibers flake off). It also allowed the watercolor pencil and watercolors to be workable without soaking in to the paper. I will definitely be using this technique in the future!