Draw a circle for the head
Add a vertical center line
Add a horizontal eye line across the middle
Mark the brow line slightly above the eye line
Mark the nose line halfway between the eye line and chin
Mark the mouth line between the nose line and chin
Sketch the jawline from the sides of the circle down to the chin
Shape the chin and cheeks
Place the eyes on the eye line
Add the eyebrows above the eyes
Draw the nose along the center line
Draw the mouth below the nose
Add the ears between the brow line and nose line
Refine the hairline
Sketch the hairstyle
Define the neck below the jaw
Add facial hair if desired
Clean up construction lines
Darken the final outlines
Add shading and details