I am about to move my 92 year old mother to assisted living facility. She is extremely angry. How do I do it?

I would make every arrangement before hand - then just take her to lunch and say you are visiting someone and once you are there, you conveniently disappear. If she has an iota of her mind left, and I doubt she does, you could try to explain but she will rant and rave and the battle will go on. Either sit her down and very firmly tell her this is the way it is and there is not going to be any alternative. And explain it is destroying your life and you need to live normally and in peace. She has lived your life and now it is your turn. Do NOT give in and do NOT feel guilty. Under no circumstances, no matter how tough you have to be, give in to her tantrums and anger. YOU are what is important at this stage of your life.