3: Remove and place the tray in cold water so that it sets. Your mouth tray is then perfectly moulded for your teeth. Repeat with the other tray. 2: Shake off any water and place the mouth tray into your mouth and gently bite down on it whilst sucking as much air as possible and press into and around teeth with your fingers so that the mould is as tight as possible (about 15 seconds).
eBay