You can customize your pet in varies ways.
First, there are currently 24 skins to choose from.
Be a cat, a dog, or even a farm animal.
You can do so by entering the playground, and buying a skin with virtual Meow coins.
You can learn how to earn coins in the Earning coins tutorial section.
After you've chosen your pet, you can change it's Eye colors and dress it up with a big slection of Hats, Glasses, Capes and Wings.
Some can are more are than others, and some aren't available in the shop, but can only be found while playing,