Keyword Research
First you must identify the search terms for which you would like your web site to rank well on search engines. The words are called your "Keywords."

It's important to identify these terms and use them in your site content exactly as people type them into search engines. To discover what these search terms are, a keyword research tool should be used.

There are several free tools available, such as the Keyword Selector provided by Overture or Good Keywords.

For more information on how to start compiling a good keyword list, read how to Research and Utilize Valuable Search Keywords.

Web Site Optimization
How do you integrated these keywords into your web pages? How often should the phrases be used, and in what sections of the pages? Search engines look at several different sections of a page when evaluating its content:

1. Title tag
2. Heading tag
3. meta
   Keyword and meta
   Description tags
4. Text within the Body area
5. Link text and Link URL
6. ALT attribute for Image tags (the ALT tag may be less significant than other areas of the page)

Search engines check various sections of your document for repeating patterns of keywords or phrases. Keyword density is the percentage of words on a web page that match a specific set of keywords. You want to keep your keyword density within a specific range so you are not suspected or keyword "stuffing."

Web Site Design
Looking good and being easy to use are important elements of web site design. But you also want to consider what makes a web site "friendly" to a search engine:

Site Map
Create a site map to make it easy for search engine spiders to index your site's content. Link to every page on the web site that has relevant content, and place a link to the site map on the site's home page. Also check out Google Sitemaps.

HTML Validation
Make sure the HTML code used in your website is formatted correctly. If there are errors in the code, then search engine spiders may have difficulty indexing the page's content. Use a HTML Validator to check the formatting of HTML code.
 
Develop a Site Theme
Don't overlook theme development. Organize your content so that particular themes are reinforced.

Avoid Duplicate Content
It's important to avoid duplicating content on the web site. Read Duplicate Content: How Does it Affect Your Rankings? for more information on how to avoid penalties associated with duplicate content.
 
Comply with Search Engines' Terms of Service
There are several practices to avoid to stay on good terms with search engines. Techniques like cloaking, hidden text, or spamming, for example, violate search engines' terms of service. If a site is found to be using these types of blackhat techniques, it will typically be removed from the search engine's index. Read this article for more information about practices to avoid.

Build Link Popularity
The Link Popularity of a page is a term that refers to the number of other web sites that link to that page. Search engines typically consider how many other sites link to a page as a factor in determining that page's ranking. The idea behind this is that if others link to a page, then they must consider that page's content to be valuable in some way. However, all links are not weighted equally and it's therefore important to try to encourage high quality web sites within your own theme area to link to your site. For a good overview of these concepts, read Link Popularity Considerations, and for some ideas about how to start building links read A Review of Link Building Strategies.

Monitor Performance
Once your optimized web site is online, you'll want to monitor its performance on the search engines. If the site is brand new, it should of course be submitted to the search engines, or perhaps resubmitted if necessary. Monitor the site's positions on search engines for keywords of interest to identify areas where the site is performing well and areas that can be improved. An excellent tool designed for this is WebPosition's Reporter feature. It creates formatted reports featuring graphs of positions over time, as well as useful parameters like the Keyword Visibility Index.

A web site that is positioned well in search engines should start receiving a significant number of visitors. To monitor traffic and other useful web site statistics, a web analytics WebTrends is recommended. Read Measuring Web Site Statistics as Part of Your SEO Strategy for more information about the benefits of web analytics.

Conclusion
The art of SEO is a set of skills that can be learned and implemented by anybody who manages a web site. However, proper optimization and maintenance of the site requires time and effort, and the fundamental elements of SEO discussed above must be put into practice. Those who find they do not have the time or desire to implement their own SEO program, read Outsourcing a SEO Program for some advice on how to best seek out professionals that can help..