If you have to wash your hair every day or every other day because of oil build up, you have oily hair. If you wash your hair with a very mild shampoo and you still feel you have an oily scalp, you have oily hair. If you have very very dry ends to the point of them breaking off, but you have to wash your hair every day because of a greasy build upon your scalp, you have oily hair with dry ends. In short, when you're looking at recipes on this blog with an eye to making something for your hair type, consider the state of your scalp, not the state of your ends.
Almost all of us with longer than shoulder length hair will have dry ends. If you've dyed, permed, straightened, or treated your hair in some way, you'll have dry ends. If you regularly straighten or blow dry your hair, you probably have dry ends. If you have oily hair and dry ends, and you make products thinking you have dry hair, you will never have a clean feeling scalp.
If you have oily roots, create your shampoo for that hair type, not for the dry ends. Make awesome products for the ends of your hair, like conditioners and leave in conditioners, and use those only below the scalp.
What ingredients can you include for oily hair? Check out this surfactant chart to see which ones might be good for your hair type. I like DLS and C14-16 olefin sulfonate for my oily hair, but there are other choices. Something like niacinamide, MSM, or honey matte might help to reduce oil if you have quite a lot of it, but otherwise, just choose your surfactants wisely.
What ingredients can you include for dry hair? Make sure you're using a daily use type of shampoo with some mild surfactants, like SMO taurate or polyglucose/lactylate blend. Add loads of re-fattening ingredients, like glycol distearate or water soluble oils.