I have large bins that my left over fabric goes into. Then when I get into organization mode,i start cutting. I have smaller bins for 6" square,
5", 4", 3" squares. I also cut strips of 2.5", 2", 1.5". 1" or smaller strips I keep for making fabric baskets.
I am now using 3" strips for binding so I will likely be cutting strips and squares.
You never know what you will need so I try to cut the biggest size possible, since I can always cut these smaller later if needed