It's a good idea to have a bag or backpack dedicated to your dog's 'stuff'. When you're ready to go out with your pup you can just grab the bag and know you have everything you'll need.
The bag should include:
The Basics
--bottle of water - for drinking and for muddy paws
--small bowl (the folding bowls are nice)
--paper towels
--vinegar/water (50/50) in a spill-proof bottle for cleaning up after accidents
--towel - for replacement bedding if needed or drying off
--freeze-dried food for treats or an emergency meal
--plastic bags for cleaning up; I like ziplocs best. You can turn them inside out, pick up, seal and put in the bag if necessary until you find a trash can.
Extras
--toy
--extra leash
--bottle of saline eye wash in case of sandy/dirty eyes
Overnight Trips
The doggy bag includes most of what you need. The only thing missing is food. Feeding raw is easy on the road. There are a number of options.
Freeze-dried food is extremely easy and great for short trips. You can bring a small cooler with pre-frozen portions in individual containers/bags. Take out one bag a few hours before you're ready to feed.
We've found that the food will start to defrost in the cooler on the second day, and is good through the third day. If you are stopping at a hotel, put the food in the room freezer overnight. If your dog doesn't have a problem eating frozen food, raw meaty bones can be fed frozen. If you're on a longer trip, simply stop at a supermarket and get raw meaty bones. All natural baby food veggies and freeze-dried or frozen organ meat work well if you're not bringing frozen 'mush'.