Iron Monkey Ventures

Short list of things to do for SEO

Content

1. Provide content, not just links, not just images.
2. Use meta-data to describe your site and content.
3. Check for broken links and correct HTML.
4. Fill in “alt” in your image tags.

Backend

https://www.google.com/webmasters/tools/dashboard – submit/verify your website, create a sitemap

Completing these steps will make sure you get listed on search engines and prepare you for the next steps – marketing and building links.

See Vaughns Google search engine SERP Ranking Factors SEO Checklist for a much more detailed and comprehensive list than what I have here.
Vaughn also lists things to avoid.  Which is just as, if not more, important than things to do.