Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.
Remove the wheel, remove the 2 bolts holding the caliper on, slide rotor off, put new one on, replace caliper, put wheel back on. You will probably need to push the pistons in the caliper in a bit so it will go over the new rotor. Release the handbrake when doing the rear rotors.
Careful of those drilled rotors on the street, prone too cracking on a road car