Determine the source of the leak. Ceilings may leak when water penetrates the roof or comes from a pipe in the attic that passes to a lower floor.
Clean up the source of the leak, if it is accessible through the attic. Use a mop, bucket and rags to collect any remaining standing water.
Put a bucket on the floor beneath the drip if it is not possible to access the source of the leak through an attic. Use a small nail or ice pick to pierce a small hole through the surface to allow any remaining water to flow into the bucket.
Contact a roofing professional to fix the leaky roof or a plumber for pipe problems. Cover the roof with a tarp to prevent additional water from entering the home and penetrating through the ceiling.
Let the ceiling surface dry completely. Use a putty knife to scrape away any flaking drywall or plaster. Apply stain sealer, according to the manufacturer’s directions, and then repaint the ceiling.