Here are some useful pencil strokes to use when sketching your preliminary animal drawings.
With constant pressure on the pencil, lightly draw parallel lines of roughly the same length. This is a good basic shading technique.
Shade with parallel lines, then shade over the first set of lines with strokes that go in a different direction. Crosshatching darkens areas more smoothly than simply shading in one direction.
Rub a stump over pencil shading to soften and blend. Create different effects by varying the direction and pressure on the stump.
Adding more pencil shading over a blended area can yield nice effects. Use the stump again, alternating between pencil and stump to achieve the desired texture.
Use these strokes for tall grass, weeds and strands of hay or straw.
These pencil strokes are good for flowing manes and tails.
Use these strokes for the stiff, slightly bending hairs of a donkey or zebra mane. These strokes are also good for depicting mowed grass.