The technique of watercolor consists in applying semi-transparent layers, which will be superimposed to achieve darker colors. It is painted from light to dark, that is, the white color is not painted, but the white of the paper is reserved.
One of the most used techniques is wet paper, also known as wet watercolor. It consists of wetting or moistening the paper on which we are going to paint, and then, with the brush well loaded with color, we give brushstrokes, horizontal, soft, inclined the paper so that the color runs, obtaining a gradient. Afterwards, and once the first layer dries, different bathrooms can be superimposed. If the previous baths have not dried, the colors will mix, producing, most of the time, unwanted effects. While the paper is wet, if we add colors or inks, they will tend to expand, obtaining very interesting effects. It can be done by dripping, or adding colors with the brush and tilting the paper in the direction we want to run the color.
Another is the use of color on completely dry paper, also known as dry watercolor. Soft baths are applied, superimposing one on top of the other, when the bottom layer dries. You could also use intense and final colors. In the resolution of a theme, usually, both techniques are used, wet watercolor to cover and color large surfaces, second planes, skies, etc., and the second to highlight close-ups.
The application of a color over another already dry, overlays, have a great importance in watercolor. It is considered one of the necessary processes to add abstract qualities to the color. The basic color, general color or background, will influence all the transparent colors that we superimpose.