A bit of easy colorwork creates the polka dot look of this simple ear warmer, which can be made any size to fit child or adult.
Starting with a chain that is a multiple of 4, create this headband with just one stitch, switching colors to make the dot pattern. Omit repeats of row 2 if desired to make it narrower.

To adjust size of ear warmer: add or subtract beg chain in multiples of 4.