My last haircut was in March 2001. I vow to not even trim it until it is halfway down my back. I have taken up with the trend of not shampooing my hair more than once a week. At the beginning, I used rinse-out conditioner the day I shampooed it, and used leave-in conditioner every time after I water-washed it. This was fine at first, but within a few days my scalp was a itchy. So I tried a different tactic. On Saturday morning I shampoo my hair; I use no conditioner or any styling chemicals. When it dries it is a little frizzy, but, me being a loner, there is nobody to complain. On Sunday, it is improved greatly, and by Monday morning, it is as if I had used conditioner. My hair is wavy/curly, and my bangs can stretch past my mouth. If there is an event on Saturday, I postpone it until Sunday and still look okay on Monday.
don't shampoo your hair till it's squeaky clean, and don't shampoo the part of your hair that does not touch your scalp. That's what's making it frizzy. Although the hair on your scalp is oily, the hair running down your back is relatively dry. So, the proper amount of shampoo for the former is way too much for the latter (and can usually be properly cleaned by just simply catching some of the shampoo rinsed off your head)