It may be a good idea to wait until you select your new cat before you begin shopping for supplies. For example, some items, such as food and water bowls or collars and harnesses, depend upon the size of the cat you will be adopting.
Also, be sure to find out which food your pet was eating in the shelter or foster home so that you can provide the same in the beginning, again to ease the transition. After the pet has settled in, talk with your veterinarian about switching to the food of your choice.
Once you’ve selected your pet, here’s a checklist of supplies you may need:
Necessary Items for Cats:
Food and water bowls
Food (canned and/or dry)
Litter box and scooper
ID tag with your phone number
Hard plastic carrier
Feline toothbrush and toothpaste
Brush or comb (depends on your cat’s coat length and type)
Super-absorbent paper towels
Sponge and scrub brush
Enzymatic odor neutralizer
Variety of toys (toys including catnip are a favorite)
The above information was taken from PetFinder.com.