Chopstick or stick
I have a few Fat Quarters of fabric laying around & some other scrap fabrics.
I don't really care what size the napkins are so I didn't measure exactly. I just cut straight lines so that I get a square or a rectangle.
I decided to use the same fabric for both sides.
Cut fabric to the size you want. 18x11 is what you'll get from a fat quarter piece if folded in half.
Place fabric wrong side out. Sew along edges leaving a quarter inch allowance leaving 3-4 inches to flip inside out.