What would be a good SEO strategy?

Before you write one line of code:

* Do keyword research to determine what keywords you want to target

While constructing your website you should do the following:

* Use markup to indicate the content of your site
o Optimize your <title> tags on each page to contain 1 - 3 keywords
o Create unique Meta Tags for each page
o Use header tags appropriately (H1 > H2 > H3)
o Use <strong> and <em> tags if appropriate
* Optimize your URLs
o Use Search Engine Friendly URLs (for dynamic sites)
o Use keywords in your domain (http://www.keyword1.com/)
o Use keywords in your URL (http://www.example.com/keyword2/keyword3.html)
o Use dashes instead of underscores to separate words in your URLs (keyword2-keyword3.html)
* Optimize your content
o Use keywords liberally yet appropriately throughout each page
o Have unique content
o Have quality content
* Use search engine friendly design
o Create a human sitemap
o Do not use inaccessible site navigation (JavaScript menus)
o Minimized outbound links
o Kept your pages under 100K in size
* Design the navigational structure of the site to channel PR to main pages (especially the homepage)
* Create a page that encourages webmasters to link to your site
o Provide them the relevant HTML to create their link to you
o Provide them with any images you may want them to use (although text links are better)
* Make sure your website is complete before launching it

Immediately after launching your site you should do the following:

* Submit your site to all major search engines
o Google (Use a Google SiteMap)
o Yahoo (Use the page list option)
o MSN
o Ask (Finds your site via incomming links)
* Submit your site to all free directories
o DMOZ (also powers Google Directory)
o JoeAnt
* Submit your site to relevant directories
o Find more at ISEDB
* Begin a link building campaign (attempting to get keywords in the link anchor text)
o Put a link to your website in your forum signatures
o Reply to relevant blog posts (Don't spam please)
o Submit articles to relevant websites

If you will pay to promote your website:

* Submit your site to pay directories
o Yahoo
o GoGuides
* Purchase text links from high PR (Pagerank) sites related to your site

Finally, as part of an ongoing strategy:

* Continually update your website with quality, unique content
* Continually seek free links preferably from sites in your genre

Do NOT do the following:

* Make an all Flash website (without an HTML alternative)
* Use JavaScript for navigation
* Spam other websites for incomming links
* Launch your site before it is done
* Use duplicate content
o Point several domains to one site without using a 301 redirect
* Use markup inappropiately
o Style <H>eader tags to look like regular text
o Hide content using 'display: hidden' (for the sake of hiding text)
* Use other "black hat" techniques (unless you accept the risk - Banning)
o Doorway/Landing pages
o Cloaking
o Hidden text
o Keyword stuffing

Additional Tips:

* Usable and accessible sites tend to be search engine friendly by their very nature
* Be patient! High rankings don't happen overnight
* Don't obsess with any one search engine. They are all worth your attention.