If you want to change your limp hair into wild, carefree curls, you're going to have to alter your hair's natural chemistry. Curls are made by two kinds of chemical bonds that cause the hair to bend: disulphide and hydrogen bonds. You're either born with plentiful disulphide bonds (i.e. naturally curly hair) or you're not, and the only way to change that is with expensive chemical treatment (a perm). Fortunately, you can "mold" the hydrogen bonds, convincing your hair to act curly for a day or two. That's all that curling hair really is. Here's how to make it happen.
