I use this pattern frequently for charitable causes.

Can be finished off with 2 rounds half double crochet rib, as in the plain light gray cap.

The blue/yellow striped hat was inspired by the color scheme of the crocheted hats worn by Sweden’s Olympic athletes during the Opening Ceremonies. (Note: this is not the hat worn by the athletes, but I wanted to use the color combo in a project.)

I worked the pattern to the 77 st point, changing the 4 colors at random in this sequence:
5 rnds off-white
1 rnd black
2 rnds pale yellow
4 rnds baby blue
2 rnds off-white
2 rnds pale yellow
1 rnd black
5 rnds baby blue
3 rnds pale yellow
2 rnds off-white
1 rnd black
4 rnds baby blue