And it's not so hard. Every dog owner knows that the dog should be fed, once or twice a day according to your routine. Good dog owners know that dogs need exercise. That's about it.
But if you want a healthy, relaxed dog, there's more.
For a start, there's the walk. A friend with a guide dog tells me that her vet insists that her dog have daily walks, off-duty. "The sniffing dogs do is essential to their health," he told her. "No matter how much exercise your dog has, it's not enough without that walk where the dog can sniff and pee and walk and mark the trail. It doesn't even have to be a very long walk, if your dog gets other exercise, but a sniff-walk is necessary for a healthy, happy dog."
There's the way in which the dog is fed. Either you share the feeding experience, by doling it out in bits, which dogs usually enjoy - they love the interaction - or you eat yourself, then give the dog its food affectionately, and walk away. Don't stay there staring; this is unnerving and not good for a dog's digestion.
And play. Every dog from a six-week-old puppy to an 18-year-old aged gentlewoman, loves to play, and should have a daily session of play that's suitable for its age and abilities. Tug-of-war, 'fetch', chase - any game where you interact together for fun.
And finally, the evening grooming. In wolf and wild dog packs, the dogs groom each other in the evening, licking each other's faces, ears, necks and shoulders. It's probably not a great idea to lick your dog, but an evening session of petting, which can be done with a brush if your dog loves being brushed, will have an enormously calming and settling effect on your dog.