You can help him by making sure he is getting the proper treatments (the best outcomes are typically a combination of medications and therapy - and exercise and good food also help in positive outcomes. Any drug abuse is going to make things worse - so helping him avoid those is also going to be a great help.
What state are you in?
I recommend you phone your local NAMI office to make sure you know of all the treatment and assistance options available to you.
Also - check out the list of early psychosis treatment centers - these are frequently the best places because they are supported by experts in treatment and are free and comprehensive: