[A]s neuroscientist Head says: "Everything you do for a dog to help them age well, you should do with them."
So eat the best food you can afford. Go for a walk, even if it's raining. Take a lot of naps. Keep your teeth clean and your breath fresh, so that the people you lick will not flinch. And when someone you love walks in through the door, even if it happens five times a day, go totally insane with joy.