Select your pet and give it a name, and then food and toys, and never forget to do it or your pet will become noisy and destructive!
When you click on the menu you'll see emerging texts indicating needs (food, water, etc.), fun (toy puppet, etc.) or training (talk, sit down, good dog, etc.). You have to select the right items according to the status of the pet at every moment. The owner's icon, visible on top, will give you useful advices while you play.