brake rotor/pad replacement for 91 protege

I need some help with the procedure of replacing the pads and rotors for a 1991 Mazda protege. All of the the wheels are disc brakes. I think i can figure out how to do it, but i would rather have some background knowledge before i just start tearing through it. Also, i don't know how to get the calipers off of the back brakes. any help would be appreciated.