Start out with a basic sketch of the eyes and eyebrows. Use an HB pencil.
Draw in a few eyebrows and eyelashes. These will help guide your lines in the following steps. An F or B pencil works well for this.
Draw in the rest of the eyelashes by following the previous step's guidelines.
Draw in the rest of the eyebrow hairs and darken the pupils a bit.
Use a cloth or a blending stump to roughly darken the drawing.
Use an eraser to lighten the highlights and a 2H pencil to define some of the soft shadows.
Use a 2H pencil to define and shade in the irises. Don't worry about darkening the pupils yet.
Finish up the drawing by using an F or B pencil to add dark shading to the irises and pupils.