Remove furniture from the room for ease of maneuvering. Cover all surfaces, including the floor, with a plastic tarp. Remove light fixtures or cover them with protective material.
Set up temporary lighting to illuminate the room. Use painters' lights or other lighting that dust can cover.
Put on safety goggles and work gloves. Wear a coverall when concerned with damaging your clothing.
Fill a spray bottle with water. Moisten a section of the ceiling by spraying it with the spray bottle.
Scrape a small section of ceiling stucco with a small utility knife. Place the large utility knife on the portion of ceiling that has the small area of popcorn removed. Hold the knife at a 30-degree angle, or less. Put even pressure on the knife and push it forward to scrape the popcorn off the drywall.
Repair gouges in the ceiling with spackle. Let the spackle dry, and then sand it with a light sand paper to smooth it into the surrounding ceiling area.
Prime the ceiling with an oil based paint to seal the drywall. Follow the primer coat with a layer of paint in your choice of sheen and color.