Using a grid to draw a side view of the head
The same proportionate guidelines that apply to the skull in a frontal view will help you draw a realistic head in side view. The only drawback to using a grid is that it can lead an artist to think of the head in terms of straight lines. This is particularly dangerous in the side view. To avoid drawing profile views of characters that look pushed up against a wall, remember that the face is positioned on a curved surface. The grid lines may be straight, but they're there to help you draw gently curved lines.
Start with the same grid you used for a front-view drawing. This time, though, don't omit the outer eighths. Draw an oval bounded by the left, right, and top edges and the “mouth line” (one-third of the way down from the bottom quarter). Indicate the jaw by drawing a curved line down from the outer edge of the circle to the bottom. The jaw line extends all the way back to the bottom of the circle in a gradually sloping line.
You'll notice that the features fall on the same grid lines. The eye is positioned on the centerline, about one-eighth from the edge of the circle. From the side, the eye's shape is best described as a sideways V. The ear is positioned on the vertical centerline, reaching from just above center to the bottom quarter line. Observe how the jaw line leads directly to the ear. The cheekbone extends from the top of the ear to the mouth. The nose extends outside the grid, reaching from the centerline to the bottom quarter. The mouth gets positioned about a third of the way down the bottom quarter.
The most difficult aspects of drawing a head in profile are the nose and mouth. Many beginners tend to overemphasize the nose. The nose juts away from the skull and, really, is a rather small feature. It also “pulls” the mouth away from the skull. Draw a diagonal line from the tip of the nose to the jaw line to help judge how far the lips should come out. Finally, add details like nostrils and a chin.
Nostrils are a big part of why beginners have trouble drawing the nose. Remember, the openings point down — not out — from the nose. The rest of the nostril is built around this opening.