There are two colored pencil technique secrets to building up layers of colors. The first is to maintain the texture of the paper. Choose a paper sith some tooth or fine texture for pencil drawings. The tooth of the paper catches and holds the pencil. As long as this tooth exists, you can add layer after layer of color. Use a light or medium touch when applying color. If you press hard, you will burnish the paper smooth creating a platform of pencil wax. Subsequent strokes will either skip across this surface without leaving color or will deposit irregular blobs of pencil wax and pigment.
The second secret to succesful layering is to use complementary colors in your shadows instead of reaching for the black pencil. Complementary colors sit on opposite sides of the color wheel: magenta and green, cyan and orange-red, yellow and violet-blue. These colors will combine with the principal color of the object to make a low chroma brown or gray shadow. The black pencil shadow is often too jarring and does not feel like a part of the shaded object.
Click on the first image to start a step-by-step sideshow.
Rough in a sphere with loose gestural lines, slowly refining them to make the ball round. Indicate the location of the highlight.
Add a complementary color for the shadow, true blue.
On top of the shadow, I add layers of scarlet red (a dark orange hue). I am care to keep a light to medium touch, maintaining the texture of the paper. Notice the little white spaces throughout the drawing. These are the diviots in the paper. As long as you can see these white flecks, you know you still have tooth in the paper. The blotches are an indication that I am starting to push too hard.
Now I add layers of other colors, yellows, reds, and greens. It is the dance and sparkle of all of these hues together that makes colored pencil drawings glow.
I now begin to blend and brighten the colors with little circular strokes of a colorless blender. Look at the difference between the blended and unblended portions of the sphere.
The blended sphere. It will be hard to add more colors on top of the blended area because the paper is burnished out. Blending is the last step in a colored pencil drawing.
Too much of a good thing… If you keep blending you will start to rub the color off your drawing. Note the pale holes appearing in the shadow area. You have to quit while you are ahead.