I build websites for a number of people, and i get asked ALL the time, what are the essential SEO changes to make.  The fact is, this is a hard question to answer, because you could optimize every single word and chances are there could be more you could do.

However, there is a short list of things that I consider the very most basic SEO essentials.  These are changes every website should make regardless of it's purpose, design or reason for being online.

1. Meta Tags
2. IMG Tags
3. Head Tags
4. Sitemap
5. Generic content pages

Sounds simple enough, right?  That's because it is.  I'll explain.