Search Engine Optimization or SEO, is a method of website promotion focused on helping your website rank favorably on Internet search engines under targeted keywords and phrases that are most important to your business and your customers.
SEO is a way of making sure potential customers can find your web site. Research shows that Internet users aren’t likely to go past the first three pages – or top 30 results – of a search when searching for information on a product or service. Qualified optimization companies can work with your website content to ensure your site is visible in the top 30 results.

When your site is ready:

• Have other relevant sites link to yours.
• Submit it to Google at http://www.google.com/addurl.html
• Submit a Sitemap to Google Webmaster tools. It uses your sitemap to learn about the structure of your site and to increase the coverage of your webpages.
• Make sure all the sites that should know about your pages are aware your site is online.
• Submit your site to relevant directories such as the Open Directory Project and Yahoo!, as well as to other industry-specific expert sites.

Design and content guidelines

• Make a site with a clear hierarchy and text links. Every page should be reachable from at least one static text link.
• Offer a site map to your users with links that point to the important parts of your site. If the site map is larger than 100 or so links, you may want to break the site map into separate pages.
• Create a useful, information-rich site, and write pages that clearly and accurately describe your content.
• Think about the words users would type to find your pages, and make sure that your site actually includes those words within it.
• Try to use text instead of images to display important names, content, or links. The Google crawler doesn’t recognize text contained in images.
• Make sure that your TITLE and ALT tags are descriptive and accurate.
• Check for broken links and correct HTML.
• If you decide to use dynamic pages (i.e., the URL contains a “?” character), be aware that not every search engine spider crawls dynamic pages as well as static pages. It helps to keep the parameters short and the number of them few.
• Keep the links on a given page to a reasonable number (fewer than 100).

Technical guidelines

• Use a text browser such as Lynx to examine your site, because most search engine spiders see your site much as Lynx would. If fancy features such as JavaScript, cookies, session IDs, frames, DHTML, or Flash keep you from seeing all of your site in a text browser, then search engine spiders may have trouble crawling your site.
• Allow search bots to crawl your sites without session IDs or arguments that track their path through the site. These techniques are useful for tracking individual user behavior, but the access pattern of bots is entirely different. Using these techniques may result in incomplete indexing of your site, as bots may not be able to eliminate URLs that look different but actually point to the same page.
• Make sure your web server supports the If-Modified-Since HTTP header. This feature allows your web server to tell Google whether your content has changed since we last crawled your site. Supporting this feature saves you bandwidth and overhead.
• Make use of the robots.txt file on your web server. This file tells crawlers which directories can or cannot be crawled. Make sure it’s current for your site so that you don’t accidentally block the Googlebot crawler. Visit http://www.robotstxt.org/wc/faq.html to learn how to instruct robots when they visit your site. You can test your robots.txt file to make sure you’re using it correctly with the robots.txt analysis tool available in Google webmaster tools.
• If your company buys a content management system, make sure that the system can export your content so that search engine spiders can crawl your site.
• Use robots.txt to prevent crawling of search results pages or other auto-generated pages that don’t add much value for users coming from search engines.

Quality guidelines – basic principles

• Make pages for users, not for search engines. Don’t deceive your users or present different content to search engines than you display to users, which is commonly referred to as “cloaking.”
• Avoid tricks intended to improve search engine rankings. A good rule of thumb is whether you’d feel comfortable explaining what you’ve done to a website that competes with you. Another useful test is to ask, “Does this help my users? Would I do this if search engines didn’t exist?”
• Don’t participate in link schemes designed to increase your site’s ranking or PageRank. In particular, avoid links to web spammers or “bad neighborhoods” on the web, as your own ranking may be affected adversely by those links.

Quality guidelines – specific guidelines

• Avoid hidden text or hidden links.
• Don’t employ cloaking or sneaky redirects.
• Don’t send automated queries to Google.
• Don’t load pages with irrelevant words.
• Don’t create multiple pages, subdomains, or domains with substantially duplicate content.
• Don’t create pages that install viruses, trojans etc.
• Avoid “doorway” pages created just for search engines, or other “cookie cutter” approaches such as affiliate programs with little or no original content.
• If your site participates in an affiliate program, make sure that your site adds value. Provide unique and relevant content that gives users a reason to visit your site first.

Source :: Google Webmaster tools.

Once again I would like to stress on these points of SEO ………

• Hosting your site/blog on a reliable hosting company.(If you are using free services like blogger or wordpress.com then sooner or latter you will need those services which they don’t provide, so rather than wasting your time in those free services, spend few bucks on hosting & domain)
• Use css instead of color, size and font tags
• Change the link buttons or js links in to text links.
• Include your keywords in the alt tags of images.
• Use the H1 tag for page headings (you can alter the way h1 displays text with CSS)
• Get rid of the js in the code and put it in an external file.
• At the bottom of each page use menus as text links.
• Make sure your page code is not bigger than 100 K.
• Submit your site to ODP(make sure to select the right category), Yahoo Dir, and other free directories like gimpsy.com and goguides.org etc.
• Try to get as much as relevant links you can. For this write unique & interesting contents & use social bookmarking sites like digg.com, stumbleupon.com, netscape.com & del.icio.us.

There are many other tips and techniques to acquire higher position in google and other search engines for certain keywords relevant to the business of the website. I will soon update this list ……. have a happy SEO