To use this dog food, simply serve it to your senior dog according to the feeding guidelines on the package. Make sure your dog has access to fresh water at all times. Store the food in a cool, dry place to keep it fresh. When switching your dog to this new food, do it gradually over a week or so to avoid any digestive upset. Keep an eye on your dog's weight and adjust the serving size as needed. If your dog has any special health conditions, it's always a good idea to consult your vet before starting a new diet.