Have you made a hat yet? I knit up a quick little one on a 16-inch circular needle for a bald woman, who feels cold even in July. Having a bald head can make you feel amazingly cool, even on a hot day!....I only know this from her, but my short haircut in spring made me feel cold some days.
I did it in stockinette, with no brim nor ribbing to start. Very simple. (when you don't knit a ribbing to start, the edge curls up - which the woman loved).
This would also give you practice in circular knitting.
Here's the hat, started, and done: