Remove all furniture from the area and cover the flooring with plastic that is taped down before beginning this project. The removal process is messy.
Mix a batch of soaking solution. The solution consists of 1 cup of ammonia, 1 cup of fabric softener and 1 gallon of water.
Apply the mixture to the ceiling with a pump sprayer. Make certain to cover it evenly. Let it soak in for about 15 minutes and reapply. As you are working, reapply as needed to dampen but not soak the ceiling material.
Scrape the texturing, which should now be soft, with a floor squeegee. It should come off readily. Once the ceiling has dried, lightly sand to smooth the surface.
Fill in any areas that are damaged with joint compound. Sand smooth and seal the ceiling with an oil-based product. Paint the color desired.