Hola! So for my brother's 10th birthday (yayyyy!), I decided to crochet him a pokeball hat. Unfortunately, the only pattern I found was a knitting pattern, and I didn't want to bother learning how to use circular needles. =P So instead, I found a pattern for a beanie from Lion and modified it into this lovely piece below!
On the adorable, smiling birthday boy:

(okay, not so adorable in that picture)
Close-ups of the button:


And on Kirby (his other present from me), who was a much more pleasant model:

Thanks for reading!
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And here's the pattern! Let me know if anything is unclear, this is my first time writing a "real" pattern. This one was a bit tight for my brother, although his head is admittedly huge. Gauge for the main body is approximately 12 sc = 3.5 in. (I don't have the hat anymore so I'm not certain), so adjust hook size, etc. as you see fit.
Main body:
Size K hook
WITH RED
Make a ring however you choose. I usually ch 4, sl st through the first ch.
Round 1: 6 sc into ring. Sl st to first sc. (6)
Round 2: Ch 1. 2 sc into into each sc. Sl st to first sc. (12)
Round 3: Ch 1. *2 sc into into first sc. One sc into next sc.* Repeat. Sl st to first sc. (18)
Round 4: Ch 1. *2 sc into into first sc. One sc into next 2 sc.* Repeat. Sl st to first sc. (24)
Round 5: Ch 1. *2 sc into into first sc. One sc into next 3 sc.* Repeat. Sl st to first sc. (30)
Round 6: Ch 1. *2 sc into into first sc. One sc into next 4 sc.* Repeat. Sl st to first sc. (36)
Round 7: Ch 1. *2 sc into into first sc. One sc into next 5 sc.* Repeat. Sl st to first sc. (42)
Round 8: Ch 1. *2 sc into into first sc. One sc into next 6 sc.* Repeat. Sl st to first sc. (48)
Round 9: Ch 1. *2 sc into into first sc. One sc into next 7 sc.* Repeat. Sl st to first sc. (54)
Round 10: Ch 1. *2 sc into into first sc. One sc into next 8 sc.* Repeat. Sl st to first sc. (60)
Rounds 11-20: Ch 1. Sc in each sc. Sl to first sc.
CHANGE TO WHITE
Rounds 21-30: Ch 1. Sc in each sc. Sl to first sc.
FO
Button:
Size F hook
WITH WHITE
Make a ring.
Round 1: 6 sc into ring. Sl st to first sc. (6)
Round 2: Ch 1. 2 sc into into each sc. Sl st to first sc. (12)
Round 3: Ch 1. *2 sc into into first sc. One sc into next sc.* Repeat. Sl st to first sc. (18)
Round 4: Ch 1. *2 sc into into first sc. One sc into next 2 sc.* Repeat. Sl st to first sc. (24)
CHANGE TO BLACK
Round 5: Ch 1. *2 sc into into first sc. One sc into next 3 sc.* Repeat. Sl st to first sc. (30)
FO
Use tapestry needle (actually, I used my F hook because I was on the plane and forced to be creative >.>) to attach to front of hat, centering on line between red and white.
"Groove":
I don't know if I can explain this well. I slip-stitched that black line going around in a zigzag. I held the hat so the line between red and white was vertical. Starting almost under the button, I pulled a loop of black yarn through. I slip stitched on the other side. Here is a diagram that may or may not help:

If all else fails, I'd say wing it! Trust me, it's hard to get wrong.
Good luck! Please let me know if there are problems.
