First, Open the trunk and locate the general area where the taillight is located and wired, IE Right or left. Then look on the inside wall of the trunk, there should be a small area that can be removed, like a small cover. Remove the cover, this will allow you to reach inside Once inside locate a small thumb wheel type knob, un loosen it, righty tighty, lefty loosey. Once this is loosen, remove the knob. Now return to the outside part of the tail light, find an area where the plastic rim of the light cover meets the metal of the car, place your fingernail or small screwdriver in between the cover and car, gently pry enough to get a grip on the light cover and pull away from the car.
The whole taillight cover should now be removed. Now remove the bad bulb, pushing down on the bulb and turning a 1/4 turn left. Replace with new bulb, first pushing down then 1/4 turn right.