I've had several cats over the years...taken in both young and old. I always just took them and put them in the litter box and that's all it ever took. I had only one who ever used the floor and that was my husband's fault. He closed the cat up in a room and didn't realize it all night long. Next day we heard him crying and went to get him and he had messed in a corner, but I probably would've done the same thing. He headed for his water and food like a bullet. And always used the litter box after that.