How do I get naturally straight hair?

I've been thinking about this for a while as I just recieved a hair straightener a month ago for my birthday and have been straightening my hair every two or three days. My mom has already warned me about what will happen to my hair after a while, but if I dont straighten my hair then it spikes up and stands on end (it has a lot of short layers) My hair is already chemically straightened but it still flips out on the ends. What should I do?! I'd really love to have straight hair that doesn't flip out on the ends without damaging it in any way!