Rand Fishkin has a handy list of common SEO mistakes which one should avoid. It doesn’t matter whether your website is a popular brand or you are just starting out, Rand shares some thoughtful SEO tips. My favorites:
Bad Navigation: You want to impress your visitors with catchy site navigation built with Flash but forget that the search bots are unable to spider the flash links. If you must use Flash in your design, also include a text link so that the bots can discover the most important pages of your site.
Not Performing Keyword research: Only a few websites pay attention to keyword research while most of them publish content without bothering whether the targeted phrase is going to rank or not. This is one of the biggest seo mistake bloggers commit and should be avoided at all costs.
Canonical URL’s: Printer friendly versions of the same webpage containing the same content may result in duplicate content issues. Webmasters should implement canonical URL’s so that the bots are not confused and can easily find the original source.
Syndicating Content to Other Popular Websites: Syndicating your articles to article directories or other news blogs may be useful but not under all circumstances. If the bots discover the syndicated content on the other blog before crawling your article, your blog is at a loss and may face the duplicate content penalty. It’s better to syndicate only a part of the content with a link back to the original article.
Hidden content stored behind logins: If your website is fairly large and consists of thousands of user generated pages that are behind a login, you are missing out on additional traffic. This is because the bots can’t crawl and index pages that are behind a password.
Multiple Sites: There is no point in launching new websites, just because you want to show your visitors how big your company is. If all these websites relate to a same niche, it would be better to create sub directories within a single domain and promote them individually. All the pages will get more PR if they are accessible under a single domain.
Check out Rand’s analysis at Seomoz.org
Related tip: Best SEO practices for new blogs