seo is divided into three large pieces
First: site structure. To do site hierarchy is very clear, it is best not more than three. No dead links.

Second: the site keyword distribution. Keyword stuffing is to optimize those mistakes unknowingly, in theory, keyword density is 3-8%, 4-5% actually probably.

Third: the site outside the chain. 1, number; (including the total number and the number of different domain all, only in some sites do not promote) 2, the quality; 3, link domain weights (gov, org, com, cn); 4, links page and site content relevance; 5, the link anchor text if keyword; 6, the link text diversity (different words)

if you are a green hand and want to learn the seo step by tep,you can follow the website.
http://www.batterysale.co.nz/http://www.batterysale.co.nz/

Nice list of explanation.