...be wary of opportunities that promise you riches overnight and tell you that you can do it all free. Money is energy and it has to circulate in order to come back to you.
As in any offline business, and more so on the Internet, developing ethical and trusting relationships with your customers and the people you interact with online is essential.
Unless you sell your own products or services, the other way to earn a sustainable long term income on the net is through a legitimate affiliate marketing opportunity.