Anyone can explain certain rules which are follow in doing link building?

Anyone can explain certain rules which are follow in doing link building?

There are many specific rules to define the quality of links. I will look at following factors before submission :
-Quality of back link(PR, PA, DA must be good)
-Relevancy of the content between 2 sites
-Proper use of anchor text.
-Avoid site-wide links
-Avoid links from low-quality sites.