Long ago, I grew my hair so long I could (and did, ow) sit on it. The key is having healthy hair -- and most especially, healthy hair tips. Otherwise, some hairs break off before they can grow longer. And these broken hairs and broken (or split) ends will tangle more, which causes more broken hairs and split ends. So, eat healthy, and condition your hair every time you shampoo. But here's the most important bit: I know it sounds backwards if you're trying to grow longer hair ... But you HAVE to trim the ends slightly, maybe every 4-5 months at least, or more often if you're still getting split ends. It's the untrimmed split ends that will make it take far longer to grow out, just because more of your hair is weakening and breaking off. Plus clean non-split ends, cut cleanly, just make your hair "look" longer. When the ends fade into a fuzzy non-cut, your hair just "looks" shorter than it is.