Whether your cat is an outdoor cat or kept strictly indoors, she should wear a collar with ID tags at all times. Many an unidentified cat has ended up abandoned in a shelter after a natural disaster such as fire or flood, or even a simple accident such as a door being left open.
Your cat’s collar should fit snugly but not too tightly. You can calculate the correct size by measuring the animal’s neck and adding one or two inches. When you put the collar on your pet, you should be able to slip two fingers comfortably between it and the cat’s neck.
Be sure to get a collar with an elastic panel, or even a breakaway feature. That way your kitty won’t choke or become trapped if her collar gets caught on something.