Here is a nice simple check list of things you can do when optimising your site.
- Unique content on your site
- Unique meta titles and descriptions on every page
- Descriptive and SEO friendly page names
- Well structured content
- Make sure you link to your important content
- Use logical and descriptive internal linking
- Images with descriptive alt text
- Sign up for Google Webmaster Tools
- Sign up for Google Analytics
- Create an xml sitemap
- Create an html sitemap
- Create a 404 error page
- Make sure your domain is set up canonically
