All of my ideas have come from trial and error, reading books by other people and observing other succesful couples in action.
First off all I would like to say. Do not be in a hurry to marry. Marrying young before you have had a chance to make your financial and social mark on society will only cause many years of frustration and tears. I am not saying live together or don't. You must decide for yourself what works for you. Some people feel very satisfied in their own home with their own surroundings and belongings.
Do not be in a hurry to have children. Your child bearing experience can be so much better if you just simply wait. And first prepare a place for your little family before creating it.
I speak from experience. I for one didn't wait, and we are doing fine, things do work out, but our experience could have been much more pleasurable had we waited, and first prepared for our family. We could have avouded many stressful problems we faced along the way.
It is a wise choice to remain at home until you have saved enough money to move out on your own. Psychology teaches that men do not reach their full level of maturity until they are 25 years old. And I wholeheartedly believe it. I believe 18 years old is a premature age to send them out on their own to completely support themselves, a home, a car, bills, finances, and a career, it's a lot to figure out on their own. It is wise if they begin to bite off a little of their freedom at a time rather than trying to bite the whole bullet at once.