White vinegar works just as well as ACV and is not quite so strongly scented, and it's scent wears off much faster than ACV. Here is a pretty good tute for going no 'poo http://babyslime.livejournal.com/174054.html and a great article for water only types http://thephoenix.com/Boston/Life/40141-No-Poo-Do/. In short the baking soda and water is meant to loosen dirt and debris and emulsify head oils so that they are more easily rinsed out and the vinegar rinse is to close and smooth the hair shaft and to carry residual oils down the hair shaft to moisturize and protect longer hair. Going no' poo isn't really a paleo thing as much as it is about avoiding extra chemicals and promoting a cycle that isn't good or even useful to the health of the hair. How you clean yourself shouldn't be based on what paleo man could or could not get his grubby little hands on, it should be determined by what works for your body and it's individual chemistry.
I don't use anything at all. I haven't washed my hair since January.
I'd recommend using baking soda if you need something. I did this initially, to help the period where everything is super greasy. Make a baking soda and water paste. Wet your head. Smear the paste on and massage into your scalp.
Don't just replace shampoo with some other crap. That's not the point. The point is that you don't need anything. If you're switching to ACV because it's "more natural", then you're confused. Making ACV from scratch is hard! It's not just found on the ground like most things paleo.
I've been doing conditioner-only for a few weeks and my hair is so silky and wonderful! It sort of falls under the definition of no 'poo since you don't use shampoo, but some people might argue that using any commercial hair care product is not in the spirit. If you're not opposed to using an all natural vegetable-based conditioner, I love love love Hugo Naturals conditioner. It's a little pricey but you don't really need that much and it absolutely smells like heaven...never before Hugo Naturals have I been tempted to eat a hair care product.
I went no 'poo at the beginning of the year, using baking soda and white vinegar with less and less frequency as time went on. Beginning March 1st, I totally stopped using anything but water on my hair, and after about a week and a half my hair has been amazing; I have always had really thin, greasy hair, and it now has body for the first time ever. It is shiny and lovely, and I am never going back!
But in the interim, I definitely found that white vinegar worked well without the smell issues that come with ACV. I can only suggest going all the way! Water works great, especially if you scrub your scalp and make sure to rinse with the coldest water possible.
You could try a honey rinse. One part honey; nine parts water. Add it to wet hair, let it sit for a bit then rinse it out. You can even leave a bit in, but you'll know you've left too much when you get that sticky look.
I've heard good thing about tea rinses, though I haven't tried it myself. I believe the basic method is to boil water 30-60 minutes beforehand, throw a tea bag in and let it steep right up until washing time. I hear green and black both work really well. Some people use herbal teas, but not all of them are acidic, so you'd have to check into that. And some herbal teas will change the color if your hair a bit too.
Every time there is a mention of No Poo somewhere, there are tons of questions and comments from experience. So, I thought it might be a good idea to set up a question and answer site to help beginners, and kind of let everyone discuss the No Shampoo/Soap lifestyle, and all the different experiences and experiments we are doing.
I would like to invite you to come post on our forum to provide info and experiences.
You can swap out a vinegar rinse with an ODOR FREE citric acid rinse. I've done both and find they are as equally effective in conditioning your hair, the only difference is that the citric acid rinse has no smell. :)