Clear the space for easier clean-up. Remove all furniture from the room. Cover the floor with paper.
Wear a face mask at all times.
Spray a section of the ceiling with water using a hand sprayer. Wet the area to loosen the adhesion.
Scrape off the popcorn texture using a drywall mud blade. Hold the blade at a 45-degree angle, peeling the popcorn texture from the ceiling in a straight line. Continue until the thickest layer of the texture is removed.
Sand the ceiling with an electric sander to eliminate pits and divets.
Whip the drywall mud using a paddle and electric drill. Mix until the joint compound is whipped and the air bubbles are removed.
Wipe the whipped joint compound over the ceiling with a drywall spreader blade. Apply in long strokes, eliminating as many lines as possible. Allow to dry.
Sand the entire surface with a sanding block until the ceiling is smooth to the touch using the palm of the hand.