Place the lenses over the eyes without securing the head strap to test the goggles for a good fit and proper seal. Achieve a suction by pressing the lenses against the face.
Bend forward and face downward. Properly fitted, unsecured giggles should stay in place for 2 to 3 seconds. If they fall off sooner, try another pair for a better fit.
Press the goggles in place to create a suction and place the elastic strap behind your head, tightening to a comfortable position. When the strap is tightened too much, it can induce headaches and increase the likelihood of leaks because the lenses are being pulled away from the eye sockets.
Smear a thin bead of petroleum jelly around the outside gaskets of rubber or silicon, in an emergency, to stop leaking right before a race. This creates a temporary watertight seal. Do not smear the jelly on the lenses; doing so will decrease your vision.
Store goggles in a hard-shell plastic case, which is available at sporting goods stores, or buy a hard case for glasses from an eyewear shop. Goggles tossed in a swim bag or a protective cloth bag often will result in bent gaskets around the lenses, causing them to leak.
Re-seal gaskets that have separated from the lenses with a bead of rubber cement, taking care not to get the cement on the lenses. The cement will smear and permanently disfigure the lenses, making them difficult if not impossible to see through.
Restore bent goggles by placing in a saucepan of simmering (not boiling) water for 5 minutes on a stove. Remove the pan from the heat and leave the goggles in the water to cool. The hot water causes the goggles to reform to their original shape. This is a last-ditch effort before replacing the goggles.