2007 cobalt, amp to factory radio

I have a stock 2007 cobolt 2 door and i wanted to add an amp and 1 sub to my factory radio. I wanted to know how do i wire it the right way without it effecting anything else in my car. can anyone help me with this project?feel that bass jo!?

The easiest way is to get a line out converter and hook it to your rear speakers for signal to your amp.  You can get a remote turn on at the fuse box, and power directly at your battery.  Ground somewhere in the trunk, and make sure you scrape the paint to get to bare metal for a good ground...LOOK before you drill, then look again.  make sure that you won't drill through the fuel tank or anything like that.     ...half of the truth can be worse than a lie. <----Roger Russell said that..

I was told to use a fuse tap to turn on the amp. But i tried it and it didn't work. what fuse should i tap into in order to turn the amp on when the radio cuts on?feel that bass jo!?

 Absolutely do not tap into a fuse at  the fuse box for your remote wire........Instead pull your radio out and use a dmm to find a wire that shows  12 volts when the radio is on and 0 volts when the radio is off

thanks a lot that helped me get a better understanding on what i was doing wrong.feel that bass jo!?

now, how do i get the face off of the factory radio without breaking it and what tools do i use to get it off?feel that bass jo!?