Most Helpful Guy
Apply a bit warm oil on the scalps. Have cold showers.
Most Helpful Girl
It would help to know your ethnicity and what type of hair you have since not everyone has the same type and therefore can't have the same hair regiment.
But other than no heat, trim it twice a year to get rid of split ends. Trimming 6-8 weeks like most girls actually keeps it from getting longer. Hair grows on average a 1/4 of an inch a month so if you cut off that 1/4 of an inch of hair every month, it'll never get longer.
But there's no way to 'make' it grow faster. All you can do is retain length. Your hair is going to grow at whatever rate it's biologically programmed to grow and there's nothing you can do about it.