HAIR NOT STRAIGHTEN AGAIN!!!!?

I JUST GOT A PERM A LITTLE OVER A MONTH AGO AND MY HAIR ISN'T STRAIGHT! I WAS WONDERING IF I SHOULD GET ANOTHER PERM TODAY OR JUST GO TO THE STORE AND GET A SHAMPOO AND CODITIONER? I DON'T REALLY WASH MY HAIR, I JUST GET PERMS EVERY MONTH. I WANT TO START THIS HAIR REGIMEN FOR THE FIRST TIME AND I WANT TO DO IT THE RIGHT WAY. SHOULD I START OFF WITH A PERM OR JUST GO AHEAD AND BUY A GOOD SHAMPOO AND CODITIONER TO GET MY HAIR STRAIGHT AGAIN???? IT'S REALLY THICK AND MY EDGES ARE VERY . PLEASE TELL ME WHAT TO DO