Step 1: Making yourself filled trays. Heat the mouth tray under 80 hot water and warm it up about 10 seconds.Put the mouth tray over your teeth,use your fingers gently try till it mold your teeth,set the trays firmly against the teeth. Step 2:Compare the teeth used teeth shade guide. Step 3:Apply a thin layer of whitening gel to both mouth trays and spread evenly(0.25 to 0.4ml for each tray anymore is just wasted). Step 4:Insert mouth trays in the mouth and over the teeth,set the trays firmly against the teeth. Step 5:Have the customer insert the tray for 10 minutes or for 7 minutes,then rinse with water. Step 6:After teeth whitening,use mouth spray.It can make you fresh breath.Repeat this complete treatment 2 tines make sure you rinse dry the tray between sessions,or once a day,after 3 days,compare before and after with teeth shade guide,we can look teeth improved 7-10 shade. Package included: 10 X Whitening Gel(3ml per) 2 X Latest design thermoform single arch trays 1 X Mini cold light whitening lamp 1 X Professional 3D Teeth Shade Guide.