Step 20 (optional): For a cleaner look, erase as much as you can of the initial guide lines. Don't worry about erasing all of the guides. It's okay to leave some behind. Re-draw any final sketch lines that you may have accidentally erased.
Final Step (optional): Add some shading to your horse drawing to give it more dimension and volume. Shade in a series of curved shapes along the top part of the leg to emphasize the muscle structure. Pick the direction of the light source when shading so that the shadows are consistent with it. If you'd like, you can stop after this step for an all-white horse.
Add a cast shadow underneath. This helps ground the horse so it doesn't appear to be floating.
You can add even more value throughout your horse drawing for extra detail. Use a dark value as you shade the mane. Use vertical strokes as you shade. Use a lighter value across the middle part of the mane to represent shine. Leave a section along the front of the head blank to give the horse the typical Clydesdale/shire look. Use a medium value for the rest of the body for a Clydesdale. Or a darker value for a shire.
Clydesdales and shires are very similar breeds. Shires tend to be bigger, but without a reference point on your drawing, the differences are minimal. Vary the pressure on your pencil to get different degrees of tonal value. If you're drawing a shire horse, the white on the legs should not go above the middle joint. Try to add the value evenly across the body for a smooth coat and avoid a rough, gritty texture. Use a light value to create a thin section along the back to give the horse's coat sheen. Shading can be very time-consuming, so be patient and take breaks.
Continue adding the value until the horse's entire body is shaded. You can add the value to different sections of the body at a time to break up the shading process. It's always a good idea to use reference as you draw. If you own a horse, try to duplicate its coat on your drawing! Remember to pause the video after each step to draw at your own pace.