Look in the carpet/throw rug section of Walmart, or which ever big box store you have, for a closed cell foam floor mat. They are like camping mats or exercise mats - which you could also use but you won't have as much waste with the floor mat. The floor mats are 1/4 inch thick and have pretty designs printed on them. I use one under my embroidery machine. I can embroider in the morning before anyone is awake, with no complaints about noise. Cut it to size.