My large ones are stored under a bed in the guest room when not in use except for one that I keep on my cutting table at all times. My small ones I actually use a wooden pants hanger and hang them in the closet in my sewing room. I do that with my blocks for quilts also, that way the project is always in the same place when I need it and sometimes I just put the pattern in the hanger with the blocks if I think I won't get to it right away. I have not used the plastic clip pants hangers for the mats but have used them for the quilt blocks. I am afraid that the plastic clip ones might leave 2 marks on them or tweak them someway.