How to install '07 Cobalt Head Unit

I have a new Head unit for my '07 Cobalt and will be installnig it soon. I am currently waiting on the wire harness to arrive (the one that keeps the chimes intact). So my question is this, How do I go about getting the dash apart in order to put in the new head unit? I want to make sure not to break anything because if I do its not covered by my warranty. So does anyone know how to go about replacing the head unit? Thanks.