Remember the old saying about teaching a dog to fish...
Anyway, some thoughts:
We rely on a 5' walking leash, a 15' tie out line, and a well-fitting harness. You want a couple of methods to control your dog's wanderings. Occasionally, we are in a location where a 35' rope line tied above head height allows a leash run that gives our ACD a good range for fun & play.
After I find a good camping spot, I check the immediate area for hazards to me and the mutt, especially ground hazards. I've found broken glass, food debris, toilet paper, crack pipes at various locations over the years.
My dog is chipped and his collar has my phone number.
Sources make dog water bowls that have an interior rim to reduce spills while on the road. They are great!
Check & stock your first aid kit for items that allow you to care for your dog. Nail clippers, wrapping and suitable gauze for bandages, Benadryl for stings/bites.
We find a wide range of terrain in our travels. Protective dog "booties" are available that are easy to put on your dog and they really help avoid stickers/cactus thorns/rock cuts to your dog. Also, helpful when on pavement in hot temperatures:
I've got a battery powered fan that I use on occasion to ventilate my truck if my dog has to remain inside. A sun blocking visor for the windshield helps too. I plan typically to do this very early in the day or after sundown. I am very careful about leaving OZY in the truck...they overheat quickly.