You are very wise to remove this "crap", excuse me. I just detest popcorn. you cannot clean it, it takes quite an undertaking to paint it, and you cannot patch it properly.
What you should know is that this is a big mess. you need to carefully tarp each room out well. you will have this stuff all over the home. Make a tent out of each room so that the powder and debris will not float all through the home. To do this seal off the door openings to the work room with visqueen or plastic. When done with that room, you should go ahead and texture that ceiling while you are there. There are prep procedures befor you do this.
They are: use a good primer for the coat over the stripped ceiling. Float out the ceiling with new mud and do your crows foot design. This is more commonly used and easy to patch.
To strip the stuff off, go to your home center and buy a long handled floor tile scraper. The handle is about 6 foot long, and the blade is about 14 inches wide. you can really get a hold of the job this way and your working on the floor standing up with out the need for ladders.
Make sure with this tool that you do not gouge the ceiling rock. This will only cause you more tape and bed work that you should not do.
With some practice, determine the right angle of the blade and just make neat swath cuts and the stuff with just fall off.
use a breathing mask. WHEN WORKING NEAR YOUR RETURN VENTS OF THE AC, BE SURE AND SEAL THEM OFF AND TURN OFF YOUR UNIT. YOU DO NOT WANT THIS STUFF SUCKED UP INTO YOUR SYSTEM. REMEMBER, SEAL OFF THE RETURN AND MAKE SURE THE UNIT IS OFF. IF THE UNIT IS ACCIDENTLY LEFT ON, THE AC WILL CHOKE FOR AIR AND AGAIN RUIN THE UNIT.
WHEN YOU TURN THE UNIT BACK ON, BE SURE AND REMOVE THE VENT BARRIERS.
Get ready for a major home wrecking job and have patence. I would sit down after reading this and decide if you are sure you want to do this. It is easy to remove, but a mess in the process.
let me know if you have any ongoing questions as you tackle this job. you can reach me on my site: www.connect.net/sjones