Make Love to Your Ends
Your ends are the oldest part of your hair. It's at the ends hair usually breaks off, splits and is the driest. Just like we should respect out elders we should respect our ends. Depending how long your hair is your ends may be several years old and has probably been through a lot. Give your ends lots of love and they'll repay you by not breaking and therefore helping your hair become longer.
Lots of naturals swear by protective styles. Protective styles are hair styles where the ends of your hair is tucked away; usually updos or even weaves or extensions (the last two I'd only recommend if your hair is at it's healthiest). There are numerous protective styles you can try, just google or YouTube!
Another way of showing your ends love is to focus in on them when you apply product. Make sure your ends get as much product as he rest of the hair. Since your ends are the part of your hair that touches your clothes when it's longer and because of it being the oldest part of your hair it gets dry easily. Focus moisture on your ends! I'm not a big fan of oil in my hair, but I seal my ends with an oil because I know they need it.