Subtle knit-purl chevrons keep this headband from curling. As much as I would like a stretchy, thin, band of stockinette to tie around my head, I know all I would get is a plump, rolled up tube of stockinette. The chevron pattern is a good second choice and lies perfectly flat with no fuss. In the loose gauge, you can only just see the difference.

This uses much less than a whole ball. The instructions are both written out line by line and charted, so you can use whichever you choose.