Remove as much furniture as possible from the room and cover the entire floor and any remaining furniture with a drop cloth or plastic sheeting.
Use your spray bottle to thoroughly wet the ceiling section you wish to tackle first. Wait about 10 minutes for the liquid to soak in.
Scrape away the textured material with the floor scraper. It should slough off fairly easily, leaving the wallboard beneath it intact.
If the ceiling is coated with primer, sand the surface with a pole sander. If you have exposed, paper-covered wallboard, skip the sanding.
Repair any holes or gouges in the wall board with your drywall compound. Apply the compound in thin layers and use the drywall blade to smooth any uneven surfaces.
Smooth over the ceiling with a damp sponge, then prime and paint.