I think "shave" might not be the correct term to use here. You don't want the hair THAT short.

Unless you want your dog to get sunburned!
It's easy if you get some really good electric clippers. I used to mainly do the underside, the legs, and the ears, on my golden retriever.
Scissors will work too, and always bring a pair of scissors on your hunts, so you can cut out tangled, matted hair, and burrs.