How do we encourage more people to care to conserve?

Unfortunately many people refuse to let themselves believe that all this is very real and not much you can do will change their mind, also unfortunately we are all going to be victims of their as well as our own, shortsightedness. We were told about this 30 years ago and we've wasted all that time, where we could have been doing something, but we went out and built huge houses ( without solar features ), we bought ever bigger trucks etc., and all the while this information was right in front of us but nobody believed it, so it's no wonder that many still don't believe it.