Find a topic or a niche to start writing about. Research and really delve into the niche. Get down to the nitty gritty to get all aspects of your target market audience. Write as much down as you can about everything in your niche so that you can expand your articles on those topics later.
Optimize keywords. Use a keyword tool like Wordtracker, a free tool for keyword optimization that will really make your articles pop on the search engines. The site is http://freekeywords.wordtracker.com/
Write at least 2 articles everyday. This will get you started in maximizing your monetary income. After awhile, your articles will start writing themselves and you will easily start writing way more than 2 a day.
Keep your titles and articles short, simple and to the point. Readers want information quick and fast and if they don't have it, someone else's article's are only a click away.
Use spell check, use spell check, use spell check. Check your grammer and read your article before submitting for errors, duplications and typos that spell check doesn't catch.
Market your articles through forum boards, social networking sites (like Digg, Delicious, Google, MySpace, FaceBook), your blog and people you know. Network as much as possible to get people to your articles.
Have fun! If you do not like what you are writing about, then you might as well not be writing because it will show. Your topics need to be something you are interested in and become an expert in what you write. Never write your articles like cheap sales copy.