Clean the areas of the shower where you plan to install the suction cups. Spray glass or tile cleaner, depending on the material, and run a squeegee over the surface until it's dry. Make sure the area is free of any soap scum or buildup.
Find suitable suction cups for the size and type of your waterproof LED lights. Some may come with suction cup mounts. Others may have a strap or similar area you can hang from a suction cup hook. Use heavy-duty suction cups to ensure the lights stay in place.
Apply rubbing alcohol to a clean cloth and wipe the shower areas where the suction cups will go. Allow five minutes for the surface to dry.
Run the back of the suction cup under warm water. Shake it free of any excess droplets. Press it immediately in place in the shower.
Hang the LED waterproof lighting from the suction cup hook or place it in the mount after waiting 24 hours from the time of suction cup placement.