Let's face it, some art media is not meant to be mixed. Look at oil paint and water-based paint. Oil and water just don't work together. Some media, however, is just made for each other. Watercolor paint and colored pencils make a great combination and compliment each other nicely.
Using watercolors and colored pencils together is a popular illustration method. When these mediums are combined, they can produce rich results. Dry watercolor can provide for a luminous base for the colored pencils, enhancing the color and texture of the layered colored pencils.
They also can be applied quickly to a variety of surfaces. Watercolor and colored pencil drawings can be applied to watercolor paper, plain paper, wood, masonite, or illustration board. The texture or tooth of the paper will affect the texture that s produced by the application of colored pencil. Coarse watercolor papers will result in broken marks with the pencils while a smoother surface like illustration board will produce more consistent marks.( In the video demonstration that follows, I use watercolor paint and colored pencils on cold pressed illustration board.)
It is also popular to use soft pastels with watercolor paint and colored pencils. The best order of application that I have found with this combination is applying the watercolor first, followed by the soft pastels. Colored pencil works best when it is applied last over the watercolor and pastel. Ink also works nicely with a watercolor/colored pencil combination.
The key to creating a rich image with watercolors and colored pencils lies in creating layers. Each of the two mediums on their own rely on layering for success. So, when they are combined, layering the color is even more important. It is also important to allow for the layers of watercolor applications to dry completely before adding either more watercolor or colored pencils. Richness in color can be achieved rather easily by applying watercolor to a surface before adding colored pencils or soft pastels.
The following video demonstrates how to use watercolor paints with colored pencils...