Step 15: 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 mountain lion drawing for extra detail. Use a dark value for the inside of the ears and a medium value for the main part of the fur. Vary the pressure on your pencil to get different degrees of tonal value. Use tiny strokes as you add the value to emphasize the fur-like texture. These small strokes should go in the general direction of the fur. They should radiate outward from the middle. For a more detailed guide on how to shade, check out this tutorial: How to shade.
Leave a couple of sections around the eyes blank. Make the inner corner of the mountain lion's eyes longer and darker. Add the value very lightly at first, and then gradually build up to the level of darkness that you want. Use a smoother, slightly darker value for the bridge of the nose and the nose itself. Use a dark value for the sides of the muzzle. Add some thin stripes here too for the base of the whiskers. The front part of the cougar's muzzle is white but add a light value at the bottom for shadows.
Separate each individual stroke a bit so that the white of the paper comes through and emphasizes the fur-like texture. Use a dark value for the lower outer edge of the mountain lion's eyes. For the insides of the eyes, use a dark value near the top and gradually make it lighter toward the bottom. Shading can be a very slow process, so be patient and take breaks. Continue adding value a little at a time until you're happy with the result.
Add some smoother shading over the short strokes to make the cougar's fur sleeker. It's always a good idea to use reference for a more accurate drawing. Add a few long strokes to the mountain lion's muzzle for whiskers. Don't forget to pause the video to draw at your own pace.