To install these tail light overlays, first, clean and wet the surface of the overlay and the tail light. A mixture of one drop of dishwasher soap and water can make it easier to align the piece. Place the overlay in the right spot and use your fingers to squeegee out the water. This helps prevent damage to the overlay. Let it sit for 24 hours so it fully sticks to the tail light. Once dry, it can withstand automatic car washes and most power washing. Keep it clean with regular car cleaning products to maintain its look.