1. First, prep the area:  Remove all furniture and items off the wall (e.g. artwork, window treatments).  Then put plastic sheets on the floor.  Extend the plastic 1 foot up the wall and attach it with painter’s tape.  This will help you later so you don’t get debris on the floor.  (Note: do not add painter’s tape to hardwood flooring as it often removes the polyurethane). I’m going to share a neat tool that will take care of most of the mess, but still, you need to cover the floors. Turn off heating/cooling vents for the area.  You’ll want to cover remove the vents/cover them with plastic (use painter’s tape to seal these).  You’ll want to do the same thing with wall outlets and switches.  Remove ceiling lights and ceiling fans.  Make sure that all of these area that may lead to electrical outlets are covered with plastic and use painter’s tape to hold in place.  You don’t want to risk getting these area wet (or dirty). You’ll also want to protect the walls, so run painter’s tape on the wall just below the ceiling and attach the plastic sheeting to it.  Overlap the plastic above the plastic that is already in place at the bottom of the wall.  Tape all sheets so nothing can penetrate behind it.  To assist with clean up, cover the floor with rosin paper.  Overlap the sheets and tape them together. 2nd you want to apply a nice coat of warm water to the popcorn ceiling. The easiest way to do this is with a standard garden sprayer. And, if you don’t have one, here’s where you can purchase one on Amazon. (They are inexpensive and can of course be used later for your flowers and garden.). It’s way easier than trying to sponge down your ceiling. Plus, since your entire room is already covered in plastic, you don’t need to worry about getting water on anything else. 3.  Let this sit for 10 to 15 minutes for full absorption.  The water is going to break down the adhesive bond and allow you to scrape it off easily.  (note: If there are many levels of paint on top, you may need to spray a second time or multiple times). 4.  After the bond has broken, you’re going to use a putty knife to scrape it off. Usually, the popcorn ceiling just peels off very easily (if it doesn’t, you’ll just want to apply more warm water).  Just glide your putty knife across the surface moving slowly with long strokes in one direction. The long, slow and even strokes will help prevent the corners of the knife from digging in and gouging the drywall.