Implementing search engine optimization into a web site is as important as the site's design, if not more so. Regardless of how well a site is designed, it is the optimization and rankings that will acquire more visitors on a day to day basis. (It is then the content and design's job to keep those visitors there.)

While optimization will help a web site no matter when it is introduced, the most beneficial approach is to keep it in mind throughout all stages of web site development, as well as to be aware of key points in site production.

Designing with Optimization in Mind
One of the easiest ways to introduce optimization is to have your designers know what will help, and what will not. While they are designers, and are focused on the aesthetic appearance of your site - there is no reason they cannot work with you to make your site more powerful for long term success.

Make sure that your designers are aware of what types of navigational features are beneficial. For example, the usage of a text based navigation will lead to much more search engine exposure than one composed of an image map or javascripting.

Beyond that, the ability to introduce headlines and other content related tags will surely help. The point of this exercise is to make sure that the design that has been used will not limit or worse yet, compromise the optimization.

Content, Clarity, and Hierarchy
If possible, your web site should contain specific information on each page. Whenever possible, your content writers and designers should avoid blending two topics into one. Each page, for the sake of optimization, should be geared towards one specific set of keywords (phrases). Having more pages on a web site is sure to help, as it will introduce more quantifiable areas for the engines to index. If each page is targeted for a specific optimization usage - extraordinary results can be achieved.

Start by putting the most broad topical categories as navigational elements. Once one of these categories is accessed, drill down further into more targeted or niche level topics. Continue that trend as much as needed to cover all aspects without becoming redundant.

Practice and Implement Validated Code
Search engines are raising their awareness to validated HTML code. While no one can immediately confirm nor deny an engines' liking to validated code, it certainly could become an issue as the Internet continues to grow.

Beyond the benefits of validated HTML code for optimization, it will also make your user base much larger. Code that goes against the W3C validation rules can often cause issues in both appearance and usability for all site users. Clearly, it would be counter-productive to employ coding that deterred any site visitors, right?

Complete the Web Site Before Launching
If you are initially designing (or redesigning) a web site, it is absolutely critical to make sure that the web site is completed. By this, I mean that all areas of content have been completed and are in place. Having a web site available to any browser (be it human, or an automated engine spider) that does not contain all of the content is simply detrimental. Without all of the unique and developed content on a page, the browser cannot understand the entire message that is trying to be conveyed. For the sake of optimization, a spider cannot effectively index your pages, and for a user, they simply cannot make logical sense as to what that page is about.

Test the Site Thoroughly
If you get to the point where the web site that is up and online (be it on a private, or public URL), it is important to test that site through and through. Run it through a series of validation programs that check for HTML validity, spelling and grammar, as well as internal and external linking. Run these reports and repair the site based on findings over and over until you pass with flying colors.

Be Prepared for Indexing Spiders (With a Robots.txt)
I have covered this previously, and again, stress it to the maximum. Before you conduct a single submission, know that a spider can come through on luck or coincidence alone. Be prepared, and let them know where they can, and cannot go the second your site goes online.

Submissions…
At long last, you have a completed, validated, content-rich, spider ready web site sitting online awaiting endless visitor sessions…. Make it happen with all of the right submissions, both paid and unpaid.