When a goggle's seal is not flush to the face, the lenses can begin to fog. When goggle lenses become foggy, they are difficult, if not impossible, to see through. Creating a tight seal is imperative to keeping goggles fog-free. Thankfully, a product like Vaseline's petroleum jelly will create such a seal, and is easily removed. Do not use vaseline when wearing goggles to protect yourself from chemicals. The vaseline can trap the chemicals.
Lay the goggles on a flat surface. The portion that goes on your face should be facing upward.
Dip your finger into the vaseline and rub between your finger and thumb to warm. Warming the vaseline will make it easier to spread.
Rub the vaseline over the portion of the goggles that touches your face. This portion of the goggles is usually rubber.
Place the goggles on your face, pressing to create a strong seal. The vaseline will help the goggles stick to your face, making it very difficult for them to become foggy.
Do not get the vaseline on the glass or plastic lenses. Vaseline on the lenses will make it difficult to see.