Professional Teeth Whitening Kit-Peroxide 4.4%How to Use Whitening Gel: Step 1: Prepare the Mouth Trays Soften the mouth trays by placing them in 7080C hot water for about 10 seconds. Remove and immediately place them over your teeth. Gently press with your fingers and lips to mold the trays to the shape of your teeth. Trim the trays if needed for a better fit. Step 2: Record Initial Shade Use the included tooth shade guide to compare and note your current tooth color before starting the