Everyone's hair is different but when hair is healthy it usually grows more. Try to use heat protecting hair spray when you straighten or curl your hair. Also if you cut it, it starts to grow faster. Hope I helped :)
When you shower is almost over (about three min. prior to getting out) turn the water's temperature up, then quickly turn it to cold. This will stimulate your scalp and promote hair growth. It also hydrates your skin and hair, and it wakes you up. (:
i know this sounds like the opposite of growing your hair, but the best thing to do is make sure you get hair cuts 2-5 months...it cuts away the dead ends which helps it grow faster. but don't cut it a lot...only a trim.
Believe it or not if you want your hair to row longer, you should have patience. To start off, just take a small trim each month and you'll find your hair growing a bit longer. This works In ways I can't really explain. This has nothing to do with having a change in your diet of your daily life. Hope this helps :)