Absolutely, yes. You can oil your hair every day. Regular oiling can help to retain the moisture in the hair strands and prevent premature greying. But there is a catch. If you have the habit of shampooing the hair whenever you oil it, this can cause a lot of damage when you do it every day. Shampooing actually removes the natural oil that your scalp secretes. So, the best thing to do is to apply only a little oil every day so that you can remove the oiliness without using the shampoo. Another method is to use very little shampoo or not to shampoo the scalp at all. Moisturising shampoos can also help a bit.