In the presence of moisture, pastels become pasty. When you moisten them more, you can use them as light washes.
What you need to know
Watercoloring, that is, using a wet paintbrush to paint with dry pastels in the style of watercolors, spreads and softens colors while keeping the lines strong.
Moistening a surface done in oil pastels with white spirit or turpentine moves color around without decreasing the tone.
Stretch a sheet of water resistant paper, such as watercolor paper.
Sketch your work with soft dry pastels using relatively thick, sweeping oblique lines.
Work the areas you have selected with a moistened paintbrush: The color will unify.
Use a very supple paintbrush to water the pigments down some more to obtain a light wash between the lines while keeping them visible.
Easily create a stippled effect on heavy grain paper: The pastels will attach to the high points while the wash will deposit a lighter color in the low ones.
Like the painter Edgar Degas, you too can turn a bit of dry pastel into powder, moisten it and apply it directly to your work.
Liberally apply the color in strong sweeping lines.
Moisten an oil painting paintbrush with white spirit or turpentine.
Brush on the pastel: its pigments will blend and the color can be moved around just like paint. Your lines will disappear and be replaced by paintbrush strokes.
You can also directly apply oil pastels to your moistened paintbrush by lifting color from the tip of a pastel stick.
