Fastest legitimate way to grow hair?

Hey, I'm a mixed girl with naturally curly hair (I've heard it's hard for curly hair to grow) I know it's not good to put heat on it, but I'd rather do that like once a week and keep it untangled throughout the week rather than wear it curly and "natural" and it gets tangled. Am I right for this? Also, please let me know of any ways that my hair can grow faster, I would like to add a couple of inches by the summertime if possible. Pleeasssee? :) <3