This article was copied from an old googlerankingsdotcom archive. I copied it in case the link changes. Though some of the details have changes slightly, this is excellent advice!
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While this document will not guarantee top placement for you in any search engines, it will increase your chances to be included in the relevant results. Consider the information below to be subjective advice, and advice only, which have been assembled based on both experience and research. Please note that all search engine technologies are constantly evolving, rendering only month-old tricks to deceive their methods useless. The only way to keep your website at a proper place of search results is - as general it sounds - providing content that people are both interested in and are looking for.

In general, search engines have been designed by people who are skilled at gathering, storing and analyzing data, programmers, mathematicians and other talented people with innovative ideas. However in the age when nearly anyone in the free world can access the internet, the ratio of people used to handling raw information have rapidly decreased. In other words, most people do not think about information the way search engine designers would.

Search engine optimization ( SEO ) is the bridge over the gap, it is to bring people with average computer skills, and the information they look for together. It overlaps the sometimes still too mathematics-based search engine technology, and takes you a step closer to your target audience. SEO should be about examining how people are looking up information on the web, and not how you may trick them into visiting your website.

1.: Choosing your Keywords
 A research done by Entireweb 31% of people enter 2 word phrases into search engines, 25% of all users look for 3 word combinations and only about 19% of them try their luck with only a single word.
   Do not choose a keyword to optimize your site for that you don't have the slightest chance of ranking good with because of the fierce competition.
   Do not choose a keyword that nobody looks for.
   Do not choose a keyword that does not relate strongly enough to your content.
   Only use generally popular keywords if you do not need targeted traffic.
   Do not use words that may get your site filtered or banned from search engines. 
   Do not use images with filenames or ALT tags ( Alt attributes of IMG tag ) that may get your site filtered or banned from search engines.
   Only use dynamic pages when the functionality demands it.
   Use lots of relevant content, well laid out into separate pages.
   For best results optimize one page for one keyword.
   Do not post half-finished sites.
2.: HTML Content
2.1.:
<.META NAME="Keywords" CONTENT="Books, Library, Author, Authors, Title, Titles, Out of print, Old Books, Rare Books, Online Library">
<.META NAME="Description" CONTENT="Online Library is a collection of rare or out of print books. Search by author, title, or content. ">
<.META HTTP-EQUIV="Content-Type" content="text/html; charset=iso-8859-1">


<.BODY>

<.H1> Welcome to the Online Library <./H1>
<.H6>. Here you will find a collection of rare or out-of-print books in electronic format. We provide you with a comprehensive search, so you can look up any book by author, title, or its content <.H6>

<.P><.H5><.A HREF="main.html">Click here to proceed to the Online Library><./A><./H5><./P>

<./BODY>
<./HTML>



Advanced SEO Advice
For established websites, refer to the Website Diagnostics articles at Googlerankings.com Diagnostics
articles by Googlerankings.com, 11.2006. through 05.2007.
Since SEO may differ for each and every sector, Internet Marketing and Search Engine Marketing trends shift on a near weekly basis, the DOs in search engine optimization are as vague as the ever-developing online supply and demand. Ethics, guidelines , written and unwritten rules of conduct are also vary for different areas, and while a less competitive sector may not require all that much effort in bringing a new website to the attention of the public, over populated areas produce new visions, methods and even spam on a daily basis.

Hence, the faces of SEO range from opportunism to great new marketing innovation, and there is no definite rule in what to do to reach one's goal. On the other hand, and especially because of this, Search Engines have to keep up their proper indexing and categorization efforts in order to provide relevant result, in which process they filter out websites from their results that are ( or are sending false signals to be ) in any way below the quality, accessibility, trust or importance thresholds. Also should a website be, or show signals of guideline breaches or illegal content, Search Engines may penalize and/or ban their presence from the search results, temporarily or permanently.

The DOs in SEO vary a lot, possibilities and combinations are infinite. One may experiment with any campaign freely, but only with a relative knowledge of the DONTs will a website be able to maintain a sustainable development plan.