Here is short list of what you need for your typical dog show. It is also available in pdf form here.
Maintaining your supplies in pre-packed containers like RubberMaid 28 gal containers makes it easier to reload prior to the trip.
Determine a packing scheme so you can load and reload your vehicle quickly. Remember you might want to stop to feed or exercise your dogs during the trip, so crates should be accessible by just opening doors. Luggage should also be accessible if you stop enroute.
If you have the luxury of extra car eg the dog van, after every show, clean out everything, and repack the car with all the non-perishable items. Remove dirty towels, pads, and mats. Remember to remove any extra bait. Loading up for the next show could involve just packing food, luggage and dogs.
Remove items that are not needed for a particular show like generators or tents for indoor shows.
When leaving, be sure to take with you:
Tack Box or Sherpa Bag:
And of course the DOG