First... DON'T blow dry your hair. It will make the frizz worse, and dry your hair out too.
I have very thick, and pretty long (mid-back) curly, wavy hair. I used to fight it, but I don't anymore.
I shower at night, every night, but I only wash my hair every other day. It took a LONG time for me to stop washing it every day even though I'd been told by hairdressers to stop.
So now, when I wash my hair I put mousse in it. Right now I'm really liking Aussie's mousse with conditioner in it. I put a generous amount in and I clip my hair up with claw clips. I just scoop it into 3 or 4 clips and go to sleep like that. It's mostly dry by morning (as long as I shower early enough), and when I let the clips out I have frizz-free curls. Be sure your claw clips don't clamp too tightly because it can give you a headache.
On the nights I don't wash my hair I let it get a bit wet when I'm in the shower.. only a little, and I still clip it up. It looks just as good as the day before.
Sometimes I don't want so much curl, and I will use the flat iron, but only after my hair is dry. I won't blow dry my hair because I can't do anything with it afterwards.
At Disney I do wash my hair everyday. I can't help that because it's so hot and my hair gets sweaty.. yuk!
I do the same thing as at home, but in the morning when I let my hair down, I then put it back up in a cute scrunchy letting all the curls just bounce around. If it's really hot I scoop it around into a bun and put the srunchy around it, and I'll steal my dd's princess tiarra hair comb (sold everywhere in Disney) and put it in front of the bun. It may be a little too princess-ey for an adult, but Hey I'm in Disney.. who cares! And it does look cute
I also bought a longer clip with Mickey ears at one end this year (again, in lots of the stores), and I rolled my hair on the back of my head with the tail facing up. I clip it with the long clip and let the top just 'flower' out at the top of my head and some of my hair falls down around the back of the clip too (remember I have long hair).
One poster said to buy the hair piece clips. You can buy the ones at disney that have small colored ribbon and small braids hanging in with the hair too. It's the same hair piece you get at the BBB.
Lots of things you can do to stay cool and look cute, even with curly, pain in the butt hair!
Have fun.