Content is KingThe web and the search engines are all about RELEVANT Content.
The articles on your website should be well written and compelling to read for your web-visitor. they should also demonstrate knowledge and impart confidence to your web-visitor. The should also contain as many of your target keywords and phrases as possible.
Regular updating and changing of your web content can also cause the search engines to visit your site more often in turn causing more links in the search engine index.
This alone can boost your natural rankings tremendously.