How to Paint a Watercolor Wash
If you are just beginning in watercolors, the first thing you need to learn is how to paint a “flat wash.” First, it’s important to have the top your pad, or a piece of watercolor paper taped to a drawing board, raised about 3 to 6 inches higher than the bottom. This allows the paint to puddle at the bottom of your strokes.
To begin, mix about a tablespoon of water with a middle tone color of watercolor paint on your palette. Red, green or blue will work fine. Use a good amount of paint to get nice color with the water. Next, fill your brush and paint a thick straight line from left to right on your paper, about four to six inches long. (Note: If you are left-handed, paint from right to left.) By keeping a full brush, there will be a puddle across the bottom of your first stroke.
Next you will replicate what you just did. This time, start at the bottom of the first stroke, picking up the puddle at the bottom of the first stroke. As you keep repeating this over and over again, keep picking up the puddle at the bottom of each stroke as you begin a new stroke. You are actually moving the puddle down the page.
When you get to the bottom of the page, or when you are finished with your “flat wash,” there will be one last puddle. Gently squeeze the excess water/paint out of your brush with a paper towel, the pull the tip of the brush across the puddle. The water will be absorbed into the dry brush. You can let your wash dry in one of three ways: 1) dry naturally, 2) dry in the sun, or 3) use a hair dryer, gently moving it back and forth over your work about 6 inches away from the paper. Any closer and you could burn it.