Healthy Hair Tip: Make sure hair is COMPLETELY dry before using a curling/flat iron. The Journal of Cosmetic Science has some pretty horrible pictures of what happens to the hair cuticle if you use a hot tool when hair is wet. The cuticle gets cracked, split and blisters up. And once you do damage like that, there's no fixing it. Be careful, kittens!
Image: Google Images
References: Journal of Cosmetic Science: Effects of thermal treatments with a curling iron on hair fiber
References: Journal of Cosmetic Science: Effects of thermal treatments with a curling iron on hair fiber