Limit the amount of hair washing you do to once a week. There is little risk of too much oil being produced to mean that you have to wash it more often to make it look clean. The only time you should wash your hair more often is if you swim or do other activities that involve chemicals getting into your hair.
In between washes, rinse your hair with water and condition it on a more regular basis. This helps to add more oils into your hair so that it constantly has a shine and looks more normal than it really is.
Leave-in conditioners have more time to work. They will be able to get into the roots of your hair and encourage more oils to be produced. There are two types of leave-in conditioners. Some are applied while in the shower while others are applied afterwards while your hair is still damp.
If you really feel you need to touch up your hair for a special occasion between washes, try a dry shampoo. This is less likely to strip all the oils from the hair and just gives it a fresher scent. Avoid using this too much as it will still strip the hair of some oils.
The chemicals in hair dyes make dry hair worse. Where possible, avoid treating your hair in this way to help encourage more oils to be produced. You could also talk to your hair stylist about the natural ways to lighten or darken your hair or consider semi-permanent hair dyes which have fewer chemicals.
The heat dries out the hair further. Protect it by avoiding it where you can. If you are going outside, use a hat and have leave-in conditioner to try and prevent the side effects of the heat. This also includes hair dryers and straightening irons. Allow your hair to dry naturally and try curlers and other methods if you really want waves. If you must use these treatments, invest in products to help protect the hair from the heat.
Some hair products use alcohol, which just ends up causing the hair to dry out further. Check the labels of any of the styling and washing products that you use to avoid them. If you must use a product containing alcohol, look for those that use cetyl alcohol. This is the most oily of all and can help to give that luxurious shine.