fill bags with water from your tank and place them into a cool box drain the rest of the water and scoop your gravel into a bag or bin and all your ornaments place heat pads in the cool box to keep your fish warm load your gear into your car and off you go. if you wish to set up your tank quickly when you arrive keep a large amount of your water in a clean bin.
I've always moved my fish in buckets, filled about 1/4-1/3 full. Personally, i haven't bothered with heating pads with my two moves, just kept the car warm for the short trip, and they were fine. Do make sure you keep your filter media wet so that you don't lose your beneficial bacteria.