On a daily basis, you can do a technique called Co-Washing. You buy the cheapest conditioner you can find (Sauve, VO5, etc) and use it as a shampoo. You have to apply a lot in order for this to work well, hence the cheaper the conditioner the better. By vigorously massaging it into your hair and scalp for 2-3 minutes, the friction created makes dirt and hair product slide off, but keeps the natural oils in place so your hair doesn't dry out. Watch this instructional vid - they're pushing their own product but the technique works for any kind of conditioner. Use a wide tooth comb as well to cover all of your hair and when you're rinsing it out.
http://www.youtube.com/watch?v=zJfEj...tailpage#t=62s You have to spend a minute rinsing it out. Then you have to follow with a real conditioner. The one below is good and not too expensive. L'Oreal Vive Pro Hydra Gloss Moisturizing Conditioner
http://www.drugstore.com/loreal-vive...195452?tab=1#1 Or, use a leave-in conditioner (Aussie, Garnier, Aveeno - all good) Then once a week use a real shampoo.