How do you install an amplifier?

First, Disconnect battery from vehicle, negative then positive. Run speaker inputs from the radio to the amp. Supply fused power from the +battery terminal connector to the amp. Ground the amp to the body/frame. Find a circuit to supply remote power (something that is only powered when the stereo is on... powered radio antenna works well). Run remote power wire from this powered circuit to the remote power input on the amp. Run your speaker wires from the amp to the speakers. Connect battery, positive then negative. Turn radio on. Test.