Use mostly text for navigation

Controlling most of the navigation from page to page on your site through text links makes it easier for search engines to crawl and understand your site. Many users also prefer this over other approaches, especially on some devices that might not handle Flash or JavaScript. having a navigation based entirely on drop-down menus, images, or animations
Avoid:
- many, but not all, search engines can discover such links on a site, but if a user can reach all pages on a site via normal text links, this will improve the accessibility of your site; more on how Google deals with non-text files.

For navigation, the focus should be on simplicity and ease of use!

Make your site easier to navigate

Create a naturally flowing hierarchy creating complex webs of navigation links, e.g. linking every page on your site to every other page going overboard with slicing and dicing your content (so that it takes twenty clicks)
Avoid:
Make it as easy as possible for users to go from general content to the more specific content they want on your site. Add navigation pages when it makes sense and effectively work these into your internal link structure.

Prepare two sitemaps: one for users, one for search engines

A site map (lower-case) is a simple page on your site that displays the structure of your website, and usually consists of a hierarchical listing of the pages on your site. Visitors may visit this page if they are having problems finding pages on your site. While search engines will also visit this page, getting good crawl coverage of the pages on your site, it's mainly aimed at human visitors.
An XML Sitemap (upper-case) file, which you can submit through Google's Webmaster Tools, makes it easier for Google to discover the pages on your site. Using a Sitemap file is also one way (though not guaranteed) to tell Google which version of a URL you'd prefer as the canonical one (e.g. http://brandonsbaseballcards.com/ or http://www.brandonsbaseballcards.com/; more on what's a preferred domain). Google helped create the open source Sitemap Generator Script to help you create a Sitemap file for your site. To learn more about Sitemaps, the Webmaster Help Center provides a useful guide to Sitemap files.

<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
<url>
<loc>http://www.brandonsbaseballcards.com/</loc>
<changefreq>daily</changefreq>
<priority>0.8</priority>
</url>
<url>
<loc>http://www.brandonsbaseballcards.com/news/</loc>
</url>
<url>
<loc>http://www.brandonsbaseballcards.com/news/2008/</loc>
</url>
<url>
<loc>http://www.brandonsbaseballcards.com/news/2009/</loc>
</url>
<url>
<loc>http://www.brandonsbaseballcards.com/news/2010/</loc>
</url>
</urlset>

Allow for the possibility of a part of the URL being removed

Consider what happens when a user removes part of your URL - Some users might navigate your site in odd ways, and you should anticipate this. For example, instead of using the breadcrumb links on the page, a user might drop off a part of the URL in the hopes of finding more general content. He or she might be visiting http://seoreadingroom.blogspot.com/, but
then enter http://www.brandonsbaseballcards.com/news/2010/ into the browser's address bar, believing that this will show all news from 2010 (2). Is your site prepared to show content in this situation or will it give the user a 404 ("page not found" error)? What about moving up a directory level to http://seoreadingroom.blogspot.com/?

Ensure more convenience for users by using ‘breadcrumb lists’

A breadcrumb is a row of internal links at the top or bottom of the page that allows visitors to quickly navigate back to a previous section or the root page (1). Many breadcrumbs have the most general page (usually the root page) as the first, left-most link and list the more specific sections out to the right

Plan out your navigation based on your homepage

All sites have a home or "root" page, which is usually the most frequented page on the site and the starting place of navigation for many visitors. Unless your site has only a handful of pages, you should think about how visitors will go from a general page (your root page) to a page containing more specific content. Do you have enough pages around a specific topic area that it would make sense to create a page describing these related pages (e.g. root page -> related topic listing -> specific topic)? Do you have hundreds of different products that need to be classified under multiple category and subcategory pages?

Make your site easier to navigate

Navigation is very important for search engines

The navigation of a website is important in helping visitors quickly find the content they want. It can also help search engines understand what content the webmaster thinks is important. Although Google's search results are provided at a page level, Google also likes to have a sense of what role a page plays in the bigger picture of the site.

Provide one version of a URL to reach a document

To prevent users from linking to one version of a URL and others linking to a different version (this could split the reputation of that content between the URLs), focus on using and referring to one URL in the structure and internal linking of your pages. If you do find that people are accessing the same content through multiple URLs, setting up a 301 redirect from non-preferred URLs to the dominant URL is a good solution for this. You may also use canonical URL or use the rel="canonical" link element if you cannot redirect.
Avoid:
 having pages from subdomains and the root directory access the same content
- e.g. "domain.com/page.htm" and "sub.domain.com/page.htm" using odd capitalization of URLs
- many users expect lower-case URLs and remember them better

Choose a URL that will be easy for users and search engines to understand!

Create a simple directory structure

Use a directory structure that organizes your content well and makes it easy for visitors to know where they're at on your site. Try using your directory structure to indicate the type of content found at that URL.
Avoid:
 having deep nesting of subdirectories like ".../dir1/dir2/dir3/dir4/dir5/dir6/page.html" using directory names that have no relation to the content in them

Use words in URLs

URLs with words that are relevant to your site's content and structure are friendlier for visitors navigating your site. Visitors remember them better and might be more willing to link to them.
Avoid:
using lengthy URLs with unnecessary parameters and session IDs choosing generic page names like "page1.html" using excessive keywords like"baseball-cards-baseball-cards-baseballcards.htm"