Polarized glasses are a “must have” item. With them on you can see straight into the water to spot fish and underwater structures. They also protect your eyes from harmful ultra-violet rays and errantly cast flies.
Polarized glasses are best worn with a cap with black bill on the underneath side. The dark underside of the hat’s bill lessens the reflected glare and gives you your best vision. Cutting down on the amount of reflected light results in less eye fatigue.
In bright conditions, amber, gray, or green lenses work well. For low light, a yellow lens is best. Because I fish more during low light, I use my yellow lenses the most.