Step 20: 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 rottweiler drawing for extra detail. Rottweilers are mainly black, so use a dark value when you shade. As you add the black value, leave certain areas, like the folds on the ear, slightly lighter to give them more shape. 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.
Leave the markings over the eyes, the eyes and the muzzle blank for now. Use strokes that go in the general direction of the dog's fur. The fur mainly radiates out from the middle. You can also start with a light value at first, and then gradually build up to the darker value. Shading can be time-consuming, so be patient and take breaks.
Continue adding the dark value all over the rottweiler's head, except for the eyes, the markings above the eyes, the muzzle and the neck. Use a dark value for the dog's eyes but don't overlap the tiny circle that represents glare. Use a slightly lighter value on the bottom of the eyes to give them a rounder look. Use a dark value for the nose, especially on the nostrils. Use a slightly lighter value for the top part of the dog's nose for highlight. Shade the muzzle using a light value and use a medium value under the nose for shadow. Use a light value for the markings over the rottweiler's eyes too.
Shade the chin and neck using a slightly darker value, especially on the creases. Add a few dots on the muzzle for the base of the rottweiler's whiskers. Use a darker value to further shape the muzzle. It's a good idea to use reference as you draw for a more accurate depiction of a rottweiler. Draw a few long strokes on the muzzle for whiskers. Don't forget to pause the video to draw at your own pace.