To prevent your dog from becoming permanently lost, make sure it wears a collar bearing your name and telephone number. This way if anyone finds your dog they will be able to contact you. It is also advisable to have your dog microchipped and register the details with the Kennel Club's Petlog database.
Make sure your dog is wormed at least once a year, preferably every three months. This will avoid a build-up of parasites which can be passed on in dog waste that is not picked up. It will also make your dog more comfortable.
If you travel with your dog in the car, make sure it has a safe, secure place to sit to prevent it distracting the driver or being injured in an accident. Always take water for your dog as walking is thirsty work. Travel with a window slightly open if possible to give your dog ventilation. When it is sunny try to park in the shade so that the car does not heat up while you are out for your walk.
The Kennel Club can give advice on all matters canine including travelling: https://www.thekennelclub.org.uk/