Route wire through or around camera helmet so that only the switch and a small length of wire is exposed.
Set your camera to the desired operating mode ("multi-exposure" or equivalent is recommended).
Place the switch in your mouth between your front teeth and aligned with the wire leading to the left or right only. Using your switch in any other orientation will damage it. Trigger the shutter release by biting gently on the red area only. Bite only hard enough to close the switch. A brief bite takes a single exposure, a longer bite takes multiple exposures.
Turn off your camera and and disconnect switch between uses.
TIPS
When you first get your switch, practice on the ground with no film. Even in the absence of a "click", you'll quickly gain the confidence to know when you have taken an exposure. Trust your teeth.
Take a test shot before each dive to verify proper functioning
Position the switch with the red dot straight up, not to the side.
Don't expose your switch to very hot or cold environments.
Turn off your camera between dives and unplug switch while not in use. Not doing this may shorten battery life.
The single/multiple exposure capabilities are dependent upon your camera. Most will take a single shot with a short bite and between 5-11 shots per second if you bite and hold. Be sure to set your camera to "continuous" or equivalent setting for desired results.
