One of the nice things about owning a cat, is that they tend to be fairly low-maintenance.
Though you should give any animal as much affection and attention as you can, once a cat is fed and has run around a bit, it tends to be content for several hours.
It is only after a nice long nap that your cat will be ready for more food and more running around. Which of course, will be followed with more napping, and so the cycle continues.
How is it, though, that they can sleep so much?
Our sense that cats sleep an inordinate amount is indeed accurate, when we judge them by human standards. In general, a house cat will spend 16 out of every 24 hours asleep. That's almost 70% of the time, and twice as much sleep as most people need. However, cats aren't lazy, they have just evolved differently than we have.
Unlike humans, cats are nocturnal hunters. In the wild they seek out prey after dark, which is also why their eyes function much better in dim light than ours do. Although a cat is awake for eight hours a day, you may not notice it, because you are asleep.
It's also interesting to remember that many of the breeds we now think of as common house cats are descended from Egyptian wildcats. When you evolve in a hot climate, one good survival strategy is to rest during the hottest hours, and become more active after the sun goes down. Also, you may want to learn to hunt and eat in quick bursts, as cats do, lying down again soon afterward to avoid overheating.