The process includes first and foremost... protection. Protection of everything. Walls need to be covered with plastic. Floors need to be covered with plastic and taped accordingly. The areas within the home or business which are having the popcorn ceilings removed, need to be compartmentalized in orde to reduce dust for traveling into areas which it is not wanted.
Once protected, you can either wet the ceilings to remove the texture or dry scrape. This process will have to be determined at the home. Once wet, the texture is simply scraped off and it falls to the floor. This is then cleaned up immediately to minimize dust travel. The ceilings are then left to dry, most likely an overnight process. After, the ceiling are floated with mud compound to protect the substrate and to provide a sand-able surface.
The following process depend on which ceiling refinished look you are wanting to achieve...would you prefer a light orange peel textured ceiling? Or would you prefer a knock-down texture placed onto your ceiling? After the finished texture has been applied, it is time to prime. Usually completed with an oil-based primer (or high stain-hiding water-based primer), this step is necessary to eliminate potential stains from the sheet rockor plaster from telescoping through the newly painted ceiling. Once this primer coat dries, 2 finish coats of paint are applied.