This page in a nutshell: It's all in the details, and there's lots of details, get yourself a cuppa to read this with.
Here, drink this.
Consistency. Keep style and formatting consistent within an article (unless explicitly excepted).
Stability. Don't change an article from one guideline-defined style to another without a very good reason.
Below is a list of some main pages which make up the Wikipedia Manual of Style. For a comprehensive descriptive directory of all the pages which make up the Wikipedia Manual of Style, see Manual of Style contents