How to jack car up without damaging side skirts?

[Boxtaboy]

Ok, it's getting close to the time when us Northeasterners need to swap our summer wheel/tires for the winter set of wheels. Usually, I have no problem jacking up the car myself and swapping the set of wheels, but this year, I'm wondering how I can do this without damaging my newly added side skirts (since they wrap under the sill area of the car). Anyone know a good method? I have a standard floor jack and hear that jack pad inserts can damage side skirts? Can I use a hockey puck instead?