Try to learn much as posible, and start by reading SEO - Search Engine Optimization | Read SEOmoz, Rank Better
How about I give you a couple of links for starters:
How search engines work:
SEOmoz | Rewriting the Beginner's Guide - Part I: How Search Engines Operate
SEO Best Practices:
SEOmoz | SEO Best Practices: SEOmoz's New Policies Based on Updated Correlation Data
I'm not an SEO expert but those are two extremely helpful posts.