I saw a hat on a stranger the other day and really liked it so, naturally, decided to try to make one like it.
This was knit on needles. The brim is K 1 row, P 3 rows, K 2 rows, P 3 rows, K 2 rows, P 3 rows and K 1 row. Then I changed to the variegated yarn and did a basic hat. The one I saw had slightly larger puffs, maybe 4 or 5 rows of purl, but I was pleased with this.
Then I wanted to make the same hat on the loom. On this hat the brim is K 1 row, P 6 rows, K 2 rows, P 6 rows, K 2 rows, P 6 rows, K 1 row. Then I switched yarn and finished the hat. This time the puffy brim was larger than I wanted but it still makes a nice variation.