I find that baking soda gets the job done. Also a mix of 1 part ACV, 1 part 3.5% H2O2, and 10 parts water makes a good shampoo (no suds, but gets clean). After rincing, I use Tea trea oil (4parts) an Lavender (1part) oil on the hair/scalp overnight and rince this out in the morning. This combo has nearly completely stopped my itchy flaky scalp as well as thinning hair (perhaps even regrowing!).
I used to have oily skin and needed a foaming soap agent of some kind. Ever since my second of five liver flushes, my skin stopped getting so oily and so baking soda works great.