The way to go is to start by rubbing the oil in to your hair starting at the roots of your hair and working your way to the tips of your hair. Leave your hair soaked in the oil for a few hours or even overnight.
Additionally, you can also add a small amount of oil to the tips of your hair every day. Applying oils to your hair also gives you the opportunity to give yourself a scalp massage!
A lot of shampoo and conditioner companies will advertising that their shampoo is perfect for your hair and makes it shine. This is usually just a marketing ploy to make you buy it and is completely false. Do research on some special shampoos and find which one works best with you.
Most people like to blow dry their hair after a shower. Stop it! This is bad for your hair and can cause a lot of damage. Instead, let it dry naturally. If you have curly hair and you straighten it using hair straighteners. Stop it! Again, this causes a lot of heat damage to your hair. Do your best to reduce the heat that you inflict on your hair.
Recommended: Best hair straighteners for preventing heat damage.
Your diet is also important. Make sure you are eating a full decent healthy meal, and replace all of those carbs with greens and fruits!