My home page bounces all over the place with respect to search engine rankings, especially from Google. First, I found a good post about optimization.
My own tips, in no particular order, are:
(0) Content, content, content.
(1) Remove HTML errors, include a good title and meta tags, target some keywords and use them appropriately, but all serious sites do this.
(2) Optimize for Google. If Google ranks your site well, so will the other engines, and most users use Google.
(3) Get links to your site listed on other reputable sites, to generate hits and improve automated reputation calculations. Don’t bother with disreputable link farms.
(4) Drop your URL everywhere, such as in web forums. You’ll get spam; deal with it.
(5) Individuals who meet Wikipedia notability standards will get an unbiased biography. Don’t create a bio for yourself because it hurt your reputation. Carefully edit Wikipedia articles.
(6) The DMOZ.org policies baffle me. Many categories are populated but never updated and they’re picky about editors. Still, DMOZ is well respected.
(7) I am an editor on syndic8.com. I reject most of the waiting feeds that I review, but there is some good stuff there.
(8) Make sure your target page loads quickly (within a few seconds).
(9) Reduce your link-to-content ratio and ad-to-content ratio. Links and ads are fine, but the search robots can pick out link farms and ad farms.
(10) Renew your domain registration for multiple years so that you don’t look like a temporary ad farm.