Navigation does more than shuttling customers around your site. In addition to its obvious usability and design functions, navigation can be optimized to improve organic search traffic. Well-optimized navigation strengthens the flow of link popularity throughout your site while sending relevant keyword signals, both of which are important to driving organic search traffic and sales.
The Power of Internal Links
Think of the aggregate power of every link that comes into every page as the lifeblood of a site. Search engine optimization professionals like to call that lifeblood “link juice.” To keep the site healthy and able to rank for the most keyword phrases possible, that lifeblood link juice has to be distributed throughout the site to feed every page. Internal links like navigation are the system of arteries and vessels that pass the link juice throughout the site.
Link juice doesn't spread evenly across a site. Most of the link juice for most sites comes into the home page as the default place to link to. Think of the home page as the heart: a big pooling of vital link juice. The farther away you get from the home page, the less link juice is passed on. Each page along the step keeps a share for itself and passes on a lesser amount. The pages at the end of the line end up with the smallest fraction.
When a page has earned links from other external sites it becomes another pool of link juice. In some cases a resource or tool your site offers can become an even stronger pool of link juice than the home page. Well-optimized navigation ensures that those pools of link juice share their strength with the rest of the site.
Optimizing Navigation Links
Global navigation, the links that appear in the templates on every page of a site, should link to the pages that have the most link juice and to the pages that you want to have more link juice. Because it’s found on every page, global navigation is the best tool to ensure that link juice is passed fairly evenly to your core pages. Typically these include category and subcategory pages that will target higher level and more valuable keyword phrases.
As new tools or resources are introduced and begin to earn links, working those pages into the global navigation will ensure that their link juice is passed throughout the site. To identify how many links a page has, check the “Traffic > Links to Your Site > Your Most Linked Content” report in Google Webmaster Tools — see "Guide to Google Webmaster Tools," my previous article. This report shows how many links each page has coming into it from external sites, and which domains those links are coming from.
Optimizing Navigation Keywords
The other important factor in optimizing navigation for SEO benefit is keyword usage. Because every link sends a keyword signal via the anchor text, every link is a chance to communicate which keyword phrases each page should rank for.
Don’t rely on your brand recognition or visual cues to set the context for the navigational keywords. If your site sells toys and “Wooden Toys” is a category of product you offer, the navigation should read “Wooden Toys” rather than just “Wooden.” It’s important to use moderation as well, though. Using exact keyword phrases for every navigational link can lead to cluttered visual experience, loss of quick customer understanding of the offerings and even spammy over-optimization. Rely on keyword research data to identify the most valuable keywords to use exactly in the navigation. Keywords that represent fewer searches can more easily be truncated.
Global navigation is an excellent tool SEO when optimized well. The most challenging aspect of navigation optimization can be balancing between usability, design and SEO needs. Don’t think of it as throwing everything out to start again, though. Look at the existing navigation with an eye to passing link juice and keyword signals. Just adding a link-juice-rich but overlooked page to the navigation or optimizing the anchor text for a couple of the highest priority pages could have a big impact on your site’s organic search traffic.