How do I make a vinegar rinse?
    Mix 1/4 cup to 1/2 cup of apple cider vinegar (ACV) with a pint of water. Experiment to find a dilution that works best for you (dry hair likes less ACV and oily hair like more). If you want to get fancy, create a vinegar rinse tailored to your hair by adding herbs and/or natural essential oils. I have included an herb and vinegar rinse and an essential oil vinegar rinse that I use below.

After shampooing apply the vinegar rinse. Massage into hair and scalp and pay special attention to the ends. Let sit for a couple minutes.
Now you have a few choices. You may rinse it all out if you want, or leave the rinse on your hair. I rinse a little--one quick spray of water. Leaving the vinegar rinse on your hair helps prevent tangles in long hair. Since the vinegar restores natural pH it also helps prevent an itchy scalp. As your hair is drying you will smell vinegar, but once your hair dries, no smell. I was skeptical at first--but this really works!

The use of vinegar with a variety of plants or essential oils for cosmetic purposes can be traced back to the Romans and was fashionable during the nineteenth century as vinegar de toilette.
The outer layer of the hair, the cuticle, covers the hair shaft and protects it like the bark on a tree. The cuticle is made of overlapping layers of long scales that lie along the surface of the hair like shingles on a roof. It is the condition of the cuticle scales that determines whether you are going to have a bad hair day.
When the cuticle is in good shape, is unbroken, and lies flat, your hair has a smooth appearance. When the layers of the cuticle are tightly knit together, the light is able to reflect off the cuticle. This is what makes hair shine! The cuticle opens when we shampoo our hair. When the cuticle layers are open and not knit together, the hair will feel rough, coarse and brittle. The hair will absorb the light rather than reflect it, which gives the appearance of dull and lifeless hair.

Vinegar removes scaly build-up and residue from hair shafts and closes the cuticles. Since residue coats the hair causing it to look dull, removing residue gives your hair more shine. By closing the cuticles, the hair slides more easily and there will be fewer tangles. Vinegar has a tonic action that promotes blood circulation in the small capillaries that irrigate the skin.