Remove the Film: Gently peel off the thin plastic film covering the lenses before your first swim.
Maintain the Anti-Fog Coating: Most modern goggles have an anti-fog coating on the inside of the lens. To help this last longer:
Avoid touching the inside of the lenses with your fingers, as the oils from your skin can damage the coating.
Rinse with fresh water after swimming in chlorinated or saltwater to prevent mineral buildup and degradation.
Air dry them before putting them back into their protective case.