This is a pretty good and quick read from Dave at the eevblog: <a href="http:&#x2F;&#x2F;www.smitselectronics.com&#x2F;assets&#x2F;files&#x2F;Library&#x2F;PCB%20DesignTutorial.pdf" rel="nofollow">http:&#x2F;&#x2F;www.smitselectronics.com&#x2F;assets&#x2F;files&#x2F;Library&#x2F;PCB%20D...</a>