Step 15: Use the remaining lines as guides to draw the rest of the beaver's body. Follow the basic path of the guides as you darken the lines to create the body. Beavers have a lot of fur, so use quick, short strokes for a furry texture. Use longer strokes at the bottom of the body to represent longer fur.
Step 16 (optional): Use the long arc on the left as a guide to draw the beaver's tail. Follow the basic path of the guide but make the end a little wider for a more paddle-like shape.
Step 17 (optional): For a cleaner look, erase as much as you can of the initial guide lines. Don't worry about erasing all of them. It's okay to leave some behind. Re-draw any final sketch lines that you have accidentally erased.
Final Step (optional): Add some shading to your 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. Don't worry too much about the shading if you're also going to add more value to your drawing.
You can add more value throughout your beaver drawing for more detail. Beavers' coats are a solid color without any pattern, so use a single value for the entire body. Beavers are dark brown. You can also color your drawing instead of shading it. Add the value by using strokes that go in the general direction of the fur. Separate each individual stroke a bit to get a coarser, more furry texture. You can also use a lighter value on certain sections of the body for a more wet and shiny look. Vary the pressure on your pencil to get different degrees of tonal value. Shading can be quite time-consuming, so be patient and take breaks. It's always a good idea to use reference for a more accurate drawing. Don't forget to pause the "How to Draw a Beaver" video after each step to draw at your own pace.
Finally, add a cast shadow underneath. This helps ground the beaver so it doesn't appear to be floating. Use a dark value near the middle of the shadow and a lighter value along the edge for the shadow's diffusion.