You just need to get the tires off the ground so that you can remove them and have access to the air springs.
For the front:
- remove the 3 bolts from the top of the "shock tower/s"
- remove the solenoid to vent the air out of the air-springs
- remove the bolt at the Lower Control Arms
- put a jack underneath the LCAs and jack them up to compress the air spring pistons
- lower the jack and the springs come out compressed
The rears are easy as all you have to do is:
- remove the solenoid to vent the air out of the air-springs
- press in the lock tabs that are under the springs & twist them until the fat lock tab at the top of the spring falls through the insert hole
- compress the spring by hand as needed
- remove air spring
Some folks have managed to get the rears done without removing the tires as you really just need to get a jack underneath to hold the car up when the springs release air.