A textured ceiling is useful for hiding imperfections that you would otherwise see if the ceiling were painted smooth. Texturing a ceiling does not require in-depth painting skills or a mastery of drywall installation techniques. Even if you are just the average do-it-yourself homeowner you can create a nicely textured ceiling in your home in a matter of a weekend.
Sand the surface of the ceiling with a 400-grit to 600-grit sandpaper mounted to a pole sander. This will add roughness for adhering the plaster to the ceiling.
Apply a 1/8-inch to ¼-inch coat of plaster to the ceiling with a plaster trowel. The thicker the plaster coat, the deeper you can make the texture. However, do not exceed ¼-inch. Allow approximately 30-minutes for the plaster to thicken up.
Roll over the wet plaster lightly with a lamb's wool paint roller. Do not press excessively hard or you will just push the plaster around the ceiling. The idea is to create small ripples of texture. The roller will load up with plaster. This is normal. Once the roller does load up though, replace it with a fresh one.
Allow at least 24-hours drying time before painting the ceiling.