Suction cups are often used to attach shower caddies and shampoo dispensers to shower walls. If the suction cups are not attached properly, however, they will eventually become loose and fall off. Fortunately, there is a way to make suction cups stick to shower walls that will keep them secure and help keep your shower items in place.
Clean the shower walls with a shower cleaner or all-purpose cleaner. Suction cups must have a smooth area to stick to and will not attach to areas where there is dirt, soap or grime. Rinse and dry the area with a clean towel.
Remove soap scum and oil from the shower walls with rubbing alcohol. Apply the rubbing alcohol in a small, inconspicuous area of the shower wall to make sure it doesn't fade the tile. Allow the rubbing alcohol to dry.
Place a small amount of petroleum jelly around the inner edge of each suction cup near the cup's outer rims. This will form a seal for the suction cups and keep the air from getting underneath.
Press the first suction cup against the wall until it sticks. Check that it is secure. Continue to stick the rest of the suction cups to the shower wall in the same manner.