How do you plan a move?

We are having to move because our landlord sold our house. It looks like we may have to be out by Nov. 15. We will also be downsizing to about 1/2 the space. I'm starting planning the move. Got the garage cleaned out and what is left are the keepers" and "garage sale" with any leftovers going to the local humane society thrift store. There is already enough to sell off and not much more can be added. I'm trying to have the sale next weekend.

Now I'm looking at the house, taking one area at a time, and sort of going by the keep, sale, throw away and give away stuff.

I need to start packing up the "keeper" stuff. Until after the probably first garage sale (there might be one every weekend as I pack).

Right now I have no place to put the keeper stuff if I start packing. Does anyone have any advice to make all this easier? A lot of the "keeper" stuff will have to go into a storage locker somewhere. I also, due to circumstance, can't have much help from my husband and have hired someone to help with all this. He just does the moving and stuff and I give him directions. he makes no decisions. Thanks everyone!