What is a least expensive way to make my natural (afro) hair grow faster?

ive been takin vitamins since i was little n still do, i dont drink ANYTHIN but water(except fo a malta frm time to time :) ) u can find me drinkin more than 5 or 6 bottles a day and i DONT even drink soda or barely juice, i exercise, eat rite, AND I STILL CANT GET MY HAIR TO GROW!! ... i use shea er to mositerize my hair and i put dr miracles n there which works well and grows ur hair but i jus hate how it smells and how it weighs down ur hair( which is y i barely use it now) wen i wash my hair i use Garnier Tripple Nutrition and to condition i use Olive Oil Replenishing Conditioner i jus dont no wat to do anymore n im a lil upset help plz????? :(