Prepare a couple boiling water in a cup of cold water.

Put the mouth guard in the boiling water for 30 seconds.

Place the mouth guard in the cold water for one second.

Place the mouth guard in your mouth around the upper teeth and press your lips with your fingers.

Press your tongue against the back of the mouth guard pushing it played against your upper teeth.

Take care not to bite through the mouth guard.

Wait about 60 seconds for the mouth guard to set then place it in the cold water one more time.