When stressed, one of my eyes start twitching, how can i lessen or prevent this?

Benign but annoying: Eyelid fasciculation or twitching is usually from fatigue, stress or even low serum potassium levels. There is no easy answer for stress related side effects except to become mentally disciplined to resist stress. Look at it this way, your body has a barometer or gauge to help warn when to relax.

Very common: Called lid myokymia; common with stress and fatigue; if becomes an issue, speak with your eye doctor. Feel better.