It may sound like an oxymoron, but it's possible for your hair to be dry and greasy at the same time. Many people have greasy roots--the part of your hair closest to your head--and dry ends because oil production happens at the scalp, according to an article in "Marie Claire" magazine. You can solve this dilemma by treating your roots differently than you do your ends.
Shampoo your hair every other day. "Marie Claire" magazine recommends not washing your hair every single day if it tends to be dry.
Use a conditioner or cream rinse on the days you shampoo. Apply it mainly to the ends of your hair, avoiding the roots. This helps prevent your roots from getting too greasy. If your ends are very dry, you can condition them on non-shampoo days as well.
Use a deep conditioning treatment once a week on the ends of your hair for additional moisture. Deep conditioners come in several forms, such as hot oil treatments, thick creams that are left in for a few minutes and washed out, or leave-in sprays.
Avoid overusing your blow dryer and/or flat iron, and limit the amount of sprays and gels you put in your hair. Using heat stylers too often can dry out your hair. Using a lot of products in your hair can make it look greasy, especially if the product is difficult to wash out.
Have the ends of your hair trimmed often to get rid of breakage and split ends. "Marie Claire" recommends a trim of no more than half an inch every six to eight weeks.