An oily scalp and dry, frizzy hair means you need to take extra care of your hair. This is because, if you use a strong shampoo to eliminate oil from your scalp, you may end up having drier hair and if you use a very mild shampoo, you will not get the oil out. But you still have options. One way is to use different shampoos for your hair — a normal one for your scalp and a mild one for your hair. This will help you keep both parts happy. But if this is too much of a hassle, you can use a mild shampoo and wash your hair twice a week to keep the oil away and not let your hair get too dry. You will have to condition your hair well, only the strands and tips and not the scalp to make it less frizzy. Another good trick is to only wash your scalp with a shampoo and not the hair every time you take a hair wash. This too will help calm the frizz.