Here's a colored pencil sketch of the Sultan's Elephant, drawn a few days ago from observation in Nantes, France. (Click on the image for a big enlargement.)
I took a picture (left) after starting the sketch to show you one way to begin a small drawing like this (about 3x5 inches). The first step was to draw the basic outlines in graphite pencil.
Then I lightly rubbed the surface with a few browns and grays in water-soluble colored pencil. Since there was no delicate detail yet, I could smudge those colors around with a water brush, keeping the white highlights on the tusk and the forehead as untouched white paper.
After that dried, I went back to define the details with a black colored pencil. The whole sketch took about 45 minutes, and I had to finish because the thing started walking.