That's it for the guides! From this point on, press harder with your pencil for a more defined drawing.
Step 11: Lightly sketch the horse's eyes inside the head as two small ovals. Use the initial lines as guides for placement. When you get the position and size of the eyes right, darken the lines. Make the sides pointier for the corners of the eyes. Make the top part of the eyes thicker and longer for the eyelashes.
Step 12: Shade the inside of the horse's eyes using a dark value. As you shade, leave a tiny circle blank to represent a highlight in the eyes. Use a lighter value near the bottom of the eyes for a rounder shape. Draw a series of short lines around the eyes for extra detail. Draw curved lines above and below the horse's eyes to emphasize the structure.
Step 13: Inside the horse's muzzle, lightly sketch two small, oval-like shapes for the nostrils. The shapes should be like irregular ovals. When you get their size and placement right, darken the lines. Use a series of curved, broken lines to create the shapes of the horse's nostrils. The nostril on the right should be smaller. Draw a few curved lines around the shapes for the outer structure of the nostrils.
Step 14: Use the small initial circle at the bottom as a guide to draw the horse's muzzle. Draw the shape of the muzzle within the edges of the initial circle. Make the shape of the muzzle narrower than the nostrils and flatter at the bottom. Draw a curved line on the left for the lower lip. Add a few lines above the nostrils for extra detail. Draw the lines above the nostrils to give the horse's muzzle more shape and structure.