- 1). Move the furniture out of the room. Cover the floor with tarps. Set up your ladder.
- 2). Scrape off the surface of the ceiling with a drywall knife to take off any loose paint.
- 3). Spread plaster over one section of the ceiling with the drywall knife, starting in one corner and coming out over an area about four feet by four feet. Hold the knife at a steep angle as you spread it, to scrape the plaster thinly over the surface. It should fill in all the indented areas while remaining paper-thin over the other areas.
- 4). Repeat for the next four-by-four section of the ceiling. Continue working your way across the ceiling section by section, scraping the knife over all of it and filling in all the indentations.
- 5). Let the plaster dry for eight hours. Assess the ceiling. If still isn’t completely flat, repeat the skimcoating process. Let it dry eight hours.
- 6). Lightly sand the whole ceiling, just enough to smooth out the new plaster. Repaint the ceiling.
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