Matt Cutts, currently the head of Google’s Webspam team, released a video on Google Webmasters Youtube channel to answer the top five SEO mistakes that webmasters make. Although these mistakes won’t destroy your rankings they will definitely hamper your progress in SEO optimization.
No domain or website for the search engines to crawl
Make sure content is accessible and not hidden away and difficult to find. Check that your links between pages are functional. Create a Sitemap for your website to tell the search engines what to crawl.
Include the right words on the page you are optimizing
Think about the words and phrases a user will use when searching. Use those words and phrases within the content of the pages. Create a menu, list your business hours, describe what you offer in a way a users is most likely to ask the search engines to look for.
Link building is an important part of optimizing your website
Matt Cutts mentions that you should create quality and compelling content and not to only think about the search engines. Remember that there are questions or concerns that the user is trying solve or learn more about. The better your content addresses those concerns, the longer each user will stay on your website.
Add a title and description to important pages
Make sure you have a title for your home page. If your site is bookmarked, what will the bookmark display? The title of your home page should be able to say who you are and what you do.
Use webmaster resources
Google Webmaster Tools and Bing/Yahoo Webmaster Tools are very valuable in your arsenal. These tools tell search engines how to index your content and provide many other benefits. Also include webmaster blogs, videos and attend webmaster conferences.