As for how, the most popular choices are content advertising like Google Adsense or referral programs like LinkShare.
As for income, it depends first on what you think of as a 'good' income. Barring, as you said, already being famous, it will take a while to build up a significant base of readers to make money blogging and those that do it for a living normally blog on several different sites. I think the guy that runs problogger said that he participated in some degree on 20 different blogs.