for some reasons on civics this is a little more difficult but what you'll need:
i forgot but i'm pretty sure a 13 mm socket
penetrant
2 (1/2 inch) nuts or four depending on how loud/ricer you want to sound, washers also work
lug but wrech
jack is needed and jack stands are highly advised

now all you need to do is jack up the car, pop off the rear tire on the right hand side, then spray penetrant on the bolts holding the muffler on to the rest of the exhaust, it should be located right behind your brakes, one your penetrating fluid has sat for a minute or two, unscrew the two bolts, then screw them back on with the nuts going through the screws, in the middle in between the two pipes