This is what I did when I had to leave my cats for three days. Made sure there are extra litter pans available in other parts of the house. Sometimes in an owners absence, cats will stress out, and not make it to the litter pan in time.
About a week before I left, I took an old pair of sneakers and put them on without socks (ewww)
and wore them around the house every day until bedtime. I sealed them up in a plastic bag, and right before we left, I put the shoes in the main room.
I cleared off all top shelves and countertops (just in case)
I lined up someone to just peek in and see that the cats were okay.
I tied the doors open so the cats wouldn't get trapped in one room.
I left water in the bathtub (not a lot) and in the sinks, as well as filled the self-feeder and water bowls.
I left pictures of all my cats on a sheet of paper and their names,and taped them to the inside of the front door- not the outside- in case something happened and people had to go look for them.
I also called my vet and let them know I was going out of town in case one of the cats ended up in his office needing help.
I got down on my hands and knees in every room and tried to figure out what I was seeing that the cats might get into trouble with, and then went about alleviating the problem.
I let my neighbors know I was leaving, and asked them to keep an eye on our place just in case.
I left a radio on a classical station on really low to help calm them.
I made sure all the cat condos were firmly anchored, (I have seen and heard of to many of them toppling over and trapping or injuring a cat.
And despite all these precautions, I worried about all my cats until I finally returned home.
*Also Louse, on stickies, we really try not to have very many in the forums. People tend to ignore them unless they are directed to them. It is just as easy to do an internal search on topics and go from there.*