I sort and store by color and type.. batiks with batiks.. traditional , and metalics. The bins are color "groupings" red, orange, yellow , brown in one bin. Green , blue , purple in another. One is just for tone on tone or muslin scraps. If it helps print off a color wheel and cut the quarter or third ( what ever works for the amount of scraps and size of bins) , and tape it to the lid or front .. so you can guide your scrap saving into the proper box.