If you own a cat, you KNOW just how they love to sleep.
In fact, cats spend a great deal of their time sleeping. The average cat sleeps for 13-18 hours a day.
Your cat probably sleeps at night when you do... sleeps most of the day while you are at work... sleeps in the evening curled up on you lap...
Cats are GOOD at sleeping :-).
Newborn kittens sleep almost non-stop. This is an inborn instinctive behavior that protects kittens in the wild. Because they sleep constantly, there is no opportunity for the babies to wander away from the birth nest. By sleeping all the time, the kittens also make less noise which might attract a predator.
As the kittens grow, their proportion of sleeping to awake time gradually changes until they reach adulthood and attain typical (for a cat) sleep patterns.
Like people, your cat will sleep more as it ages.
Unlike humans, cats spend many hours sleeping relatively lightly. A cat can go from what seems to be a deep sleep to fully awake in a matter of seconds.
You may have also noticed your cat enjoying a short nap — with its eyes half closed — or even with eyes wide open!
Cats choose a sleeping place that feels safe. What feels safe varies from individual to individual. Some cats like to be up high. Some prefer small spaces like under the sofa. Some cats like to snooze in the sunshine - some in the dark.
During hot summer days, the cat usually prefers a shaded or cool sleeping place. In the winter, most cats will look for a warm spot near a register or in the sunshine.
Temperature also effects the cat's sleeping position. When cold, cats tend to curl and put their face between their paws to reduce body heat loss. When hot they will often sleep stretched out with the belly turned upward to release the body heat.
Of course, your cat may prefer to sleep with you on your bed. Your bed is filled with your scent and so is attractive to your feline companion. And of course, letting your cat sleep on your bed can keep your toes warm and means you may fall asleep with purring in your ear - a definite stress reliever :-).

Because a cat in the wild is a nocturnal hunter, some cats will tend to sleep all day and then keep you awake wandering the house at night.
To change your cat's sleeping habits, provide plenty of stimuli during the day. Play more, especially just prior to bed time. Getting a second cat often provides more activity during the day. The more awake time your cat has during the day, the more likely your kitty will need to sleep at night.
I'd write more . . . only . . . I'm . . . (yawn) . . . getting sleepy . . .