Sorry to hear you don't like the perm. Contrary to some things you may have heard (beer, vinegar, mayo) there is no natural way to remove the perm, but there is a chemical way that is not too terribly damaging.

Get a perm kit (a gentle one for color treated hair) and comb the solution through your hair (not continual combing, just enough to saturate the hair) then let the hair process while you sit for the 15 or 20 minute time (carefully follow the timing directions). Rinse the hair and towel dry, apply neutralizer, combing through only until it is covered, leave on the hair 5 minutes and rinse out. After this, your hair will need a good conditioning pack (Redken Extreme and Nexxus Keraphix are excellent). Pack it on the rinsed and towel dried hair and go under a plastic cap for 20 minutes. Rinse and style as usual and the hair should be back to your normal non-curl pattern.

I hope this helps. Good luck!