Made: Hello Kitty Crochet Hat

My first crochet hat: free pattern from Crochet in Color

I've been slacking off on my posting. Just got back to work and it's been tiring, but I'm still crocheting along to keep me in zen mode.

Never thought I would make anything Hello Kitty, since I've always been more of a Little Twin Stars girl, but  my first hat is a Hello Kitty one, using the free pattern shared by Crochet in Color (thanks!) and it always feels good to be able to do something for your friends. Don't you agree?
Anyway, I would love some advice on how you determine the size and when to stop increasing. My first attempt, even though it seemed to be measured right, was way too big, so big that it fits me, even though I was aiming for a toddler hat. Now I'm waiting to hear if my second attempt fits or not. Crossing my fingers.
Here are some other free Hello Kitty crochet hat patterns I found: Inspirednest.ca • Crochet Creative Creations