Step 20: Draw a series of short strokes between the ears for the top part of the mane. Draw longer strokes to the right of the head for the part of the mane that stretches across the back. Curve the strokes downward to emphasize the mane draping over the body. Don't draw every single hair on the mane. Just draw a few to give the basic outline of the warthog's mane. Add some curved strokes on the sides of the muzzle for the tufts of bristles found there.
Step 21: Use the remaining lines and shapes as guides to draw the rest of the warthog's body. Simply darken the outer edges of the initial guides to create the shape of the body. Draw the shape of the tail around the guide on the right. At the bottom draw a few short strokes for hair.
Step 22: 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 warthog drawing to give it more dimension and volume. 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. Don't worry about shading too smoothly; the rough value gives the skin a bumpy texture. For a more detailed guide on how to shade, check out this tutorial: How to shade.
Add a cast shadow underneath. This helps ground the warthog so it doesn't appear to be floating.
Add a medium value throughout the entire body for extra detail. If you make the value for the body darker than the shadows, make the shadows darker. Warthogs can have light or dark manes. I'm shading mine lightly, but you can make yours darker for a more Pumbaa look :) If you're using a light value for the mane, don't overlap the medium value of the body on to the mane.
Remember that it's okay to not shade so smoothly because warthogs have rough skin covered in bristles. Shading can be time-consuming, so be patient and take breaks. It's always a good idea to use reference as you draw. Don't forget to pause the video to draw at your own pace.