Start with the outline, to make the eyes look mysterious, a lot of the eye isn't seen but under the eyelid.
Now add the pupils, make sure the pupils match each eye looking to the right.
Now shade, the eyelid is light and the crease is the darkest part. Shade upward to make the eyelids look round.
Also shade the section on where the nose bridge would join the eyes and forehead.
Now to add the mystery, add dark eyelashes. Draw each eyelash by itself in a loop starting from the eyelid, swing down, then up again to make them curve like real eyelashes. Ta da!!! Mysterious ;)
Thanks guys!!! You know I would love to hear how my guides have helped you guys :) thanks! Please comment how they have effected you :)