You will need three 1/2-by-2 3/4-by-4 1/4-inch sponges. Use new sponges, and be sure not to wet them ahead of time; they are easier to cut straight out of the package. With a pen and a ruler, make five lines lengthwise on a sponge, each 1/2 inch apart. Use scissors to cut the sponge, using the lines as a guide, into six rods. Repeat with the other two sponges. Lay strips on top of each other in three layers, five to six to a layer. Cinch them across the middle with a piece of string; knot it tightly. Fluff pieces out into a ball.
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