Step 20: Use the remaining lines and shapes as guides to draw the rest of the bull terrier's body. Simply darken the outer edges of the initial guides to create the shape of the dog's body. As you darken the lines, don't overlap the legs that are on this side of the body. Extend the line for the left edge of the hind leg upward to finish the back portion of the body. Darken the curved line on the left for the dog's tail. Add another curved line under it to complete the shape.
Step 21: 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 you may have accidentally erased.
Final Step: Add some shading to your bull terrier dog drawing to give the figure more dimension and volume. Use a dark value for the inside of the ears and for the nose. Use a lighter value for the rest of the dog's body. Add a couple of rows of dots to the left of the nose for the base of the whiskers. Pick the direction of the light source when shading so that the shadows are consistent with it. Vary the pressure on your pencil to get different degrees of tonal value. For a more detailed guide on how to shade, check out this tutorial: How to shade.
Some bull terriers have coat patterns, so you can add dark patches on the body if you don't want a white terrier. It's a good idea to use reference as you draw for a more accurate depiction of a bull terrier. If you have a pet bully or a similar breed, try to duplicate its coat on your drawing. Shading can be time-consuming, so be patient and take breaks.
Add a cast shadow underneath. This helps to ground the dog so it doesn't appear to be floating. Don't forget to pause the video after each step to draw at your own pace.