Cover the furniture and floors with a drop cloth or old sheets.
Place protective wear over your eyes, and a dust mask over your mouth and nose to protect them from falling dust or debris.
Dust the ceiling tiles with a feather duster or a vacuum with a dusting attachment. Make sure to dust the corners of the room.
Wash away any spots or stains using a sponge. You can wet the sponge with a solution of water and mild dishwashing liquid, if the tiles are made from tin or finished synthetic. Don't use water with porous or sheetrock tiles.
Scrape away rust from the ceiling tiles using steel wool.
Remove any tiles that have a water stain on them. Inspect the plumbing or area behind the panel and fix any internal leaks. Contact a professional plumber if necessary.
Wipe away the water stain with a dry sponge on a porous and sheetrock tiles, use water and detergent on other panel types.
Mix 1 part bleach with 3 cups water in a container, if the stain doesn't come out on porous or sheetrock. Dab the water stain with a soft cloth or sponge.
Pour the shellac stain blocker into a paint pan.
Roll the shellac stain blocker onto the surface of the tile with a foam roller that is split every half inch. Then allow it to dry thoroughly.
Remove the paint lid and stir the paint. Then pour the paint into a paint pan.
Apply white latex paint, or a matching white paint, to the ceiling tile with a foam roller that is split every half inch. You can just paint the damaged tile, or all of them.