Chop rosemary and place it in a jar. Fill jar with apple cider vinegar and store in a cool dark place for one week, shaking jar vigorously once a day to disperse the rosemary.

After one week, strain liquid, discard, discard rosemary and return liquid to jar.

When ready to use, dilute 1/3 cup of liquid in three cups of water and rub into freshly shampooed, damp hair and scalp. Avoid getting any mixture into your eyes. Rinse thoroughly and dry hair as usual.