Wash it with frizz controlling shampoo and conditioner rise with warm water blow dry your hair then straighten it. that's what I do works like a charm! it's temporary but you could get a straight perm.
get frizz control shampoo and conditioner. get keratin hair lotion for when you blow dry it to protect it against heat and flat iron it after you blow dry it. OR get a relaxer and call it a day, those are suppose to last a while as long as you don't get your hair wet the first 3 days.