Informntion From Google Help Center...
Things to do
Our webmaster guidelines provide general design, technical, and quality guidelines. Below are more detailed tips for creating a Google-friendly site.
Give visitors the information they're looking for
Provide high-quality content on your pages, especially your homepage. This is the single most important thing to do. If your pages contain useful information, their content will attract many visitors and entice webmasters to link to your site. In creating a helpful, information-rich site, write pages that clearly and accurately describe your topic. Think about the words users would type to find your pages and include those words on your site.
Make sure that other sites link to yours
Links help our crawlers find your site and can give your site greater visibility in our search results. When returning results for a search, Google combines PageRank (our view of a page's importance) with sophisticated text-matching techniques to display pages that are both important and relevant to each search. Google counts the number of votes a page receives as part of its PageRank assessment, interpreting a link from page A to page B as a vote by page A for page B. Votes cast by pages that are themselves "important" weigh more heavily and help to make other pages "important."
Keep in mind that our algorithms can distinguish natural links from unnatural links. Natural links to your site develop as part of the dynamic nature of the web when other sites find your content valuable and think it would be helpful for their visitors. Unnatural links to your site are placed there specifically to make your site look more popular to search engines. Some of these types of links (such as link schemes and doorway pages) are covered in our webmaster guidelines.
Only natural links are useful for the indexing and ranking of your site.
Make your site easily accessible
Build your site with a logical link structure. Every page should be reachable from at least one static text link.
Consider creating static copies of dynamic pages. Although the Google index includes dynamic pages, they comprise a small portion of our index. If you suspect that your dynamically generated pages (such as URLs containing question marks) are causing problems for our crawler, you might create static copies of these pages. If you create static copies, don't forget to add your dynamic pages to your robots.txt file to prevent us from treating them as duplicates.
Things to Avoid
Don't fill your page with lists of keywords, attempt to "cloak" pages, or put up "crawler only" pages. If your site contains pages, links, or text that you don't intend visitors to see, Google considers those links and pages deceptive and may ignore your site.
Don't feel obligated to purchase a search engine optimization service. Some companies claim to "guarantee" high ranking for your site in Google's search results. While legitimate consulting firms can improve your site's flow and content, others employ deceptive tactics in an attempt to fool search engines. Be careful; if your domain is affiliated with one of these deceptive services, it could be banned from our index.
Don't use images to display important names, content, or links. Our crawler doesn't recognize text contained in graphics. Use ALT attributes if the main content and keywords on your page can't be formatted in regular HTML.
Don't create multiple copies of a page under different URLs. Many sites offer text-only or printer-friendly versions of pages that contain the same content as the corresponding graphic-rich pages. To ensure that your preferred page is included in our search results, you'll need to block duplicates from our spiders using a robots.txt file. For information about using a robots.txt file, please visit our information on blocking Googlebot.