If you have a small or medium-sized pet, especially a dog, a car seat especially for them might be a good idea. If they like to see the sights, they’d be very happy when strapped safely into a seat and enjoying the view. This way, you can prevent them from distracting you while driving. It would also keep them safe from suddenly leaping out whenever you open a door or window.
Letting your dog stick their head out of a car window is highly dangerous, so be sure to discourage such behavior.
Of course, a waterproof car seat would also be able to contain any accidents that might occur on the trip. Travelling can mess with a dog’s training, so a dog car seat is your best option for protecting the rest of your vehicle.
If your dog is on the larger side, though, you might want to invest in car seat covers for a similar level of protection.