Jack up the car with a car jack (Not absolutely necessary but so much easier)
Remove 10 plastic screws underneath using a Torx 27 screwdriver. (pictures shows 9 as I had one missing)
Remove 2 metal screws near the rear wheel using 8mm bit
Lower the jack
Pull the skirt away from the car using either end (there is some resistance but they will snap out).
Removal takes about 10-15 minutes.
If you live in a northern state or Canada like me expect the inside of the skirts to be really dirty and with a lot little rocks( check pics) so be careful not to scratch the paint
To put back
Get the new skirt and put in all the clips (there is an indentation where each goes) then snap on the back ends first making sure that the bottom slides under the plastic underneath the car .
Then go clip by clip and push in carefully by applying pressure on the skirt
Jack the car up again
Screw everything back and your done
For those of you doing this to get rid of the rattles caused by the SWS-8 subs
Put the Dynamat on the skirts as shown in the pictures before putting back