The articles contain much of what has been suggested here, but do have some additional detail. Key additions:
…the two most important factors in your score are:
* Whether you pay your bills on time.
* How much of your available credit you actually use.
* Apply for department store and gasoline cards. These are usually easier to get than major bank credit cards such as Visa or MasterCard.
* Once you’ve been approved for one card or loan, don’t rush out and apply for several more. Applying for too much credit will hurt, rather than help, your score. Most people need only one or two bank cards, a gasoline card and a department store card, acquired over a year or more, to start a solid credit history.
* Don’t max out your credit cards. In fact, don’t even come close. Try to avoid using more than 30% or so of the credit you have available to you — even less, if you can. Your credit score measures the difference between the credit available to you and what you’re actually using. The smaller that gap, the more it hurts your score. Lenders will worry that you’re becoming overextended and won’t be able to pay your bills if you charge too much.