credit: andreasnilsson1976

A fairly robust list of popular white hat techniques for improving your search engine ranking.

1. Use Spiderable Code – HTML is best, but many others work.
2. Title Tags - Make them unique.
3. Description Tag – Use as summary of the page.
4. Image Tags – Use all 4 of the standards Height, Width, Alt & Source.
5. H Tags - Use headers for proper structure.
6. Semantic Mark-up - use bold and italics to highlight important information.
7. On Page Content - Write using the words searchers use.
8. Keyword Research – Use online tools to discover what people are searching for.
9. Site Architecture – Good internal linking will spread your link value efficiently.
10. Link Building – Generally, the more links the better. Link Building comes in many flavors.
11. Linkbaiting – Make content specifically to entice linking.
12. Submit to Directories - Many directories are still well used, but their link value is less now than it used to be.
13. Link Request – Talk to people who have a legitimate reason to be interest in your content.
14. Social Media Profiles - Many of them let you link to your site.
15. Use Forums – Participate in forums and many of them let you have a signature.
16. Make Comments on Blogs – Many link to commenter’s site.
17. Make a Blog of Your Own – This is a good way to make content on a regular basis.
18. Contribute Content to Social Media – Participating in user generated content sites will help you make more connections on the web.
19. Write Press Release – This isn’t as powerful as it once was, but it is still available.
20. Write Guest Blogs – Every blogger likes a day off and you get a chance to link.
21. Make a Widget – Be like Matt Inman, hide a bit of yourself all over the Internet.
22. Make a Credit - Lots of people accumulate links through credit links for their tools, images and design work.
23. Robot.txt - Tell the spiders where to go.
24. Site Maps – Tell the spiders where to go, in a different way, comes in 2 popular flavors XML and HTML

It is important to note: if you automate 12 -19 it is generally considered black hat.