- Sometimes a little artist's license is needed if light is poor or when working from a photo. Adding a little curved highlight cutting across the pupil and iris, a shadow under the lid, or detail to the iris, can brighten flat eyes.
- Don't automatically outline the lower lid - often the lower rim is highlighted and needs to be lightly indicated.
- Draw the subtle changes in tone which indicate the eye socket, and the planes of the nose and brows, which help to sit the eyes into the face. If using line, you can use broken or implied line.
Ultimately, the level of realism and detail that you obtain depends on observation, patience, and a sharp pencil.