you'll need cat litter and a litter box(hopefully she's litter trained)...take her to the vet...or even to the low cost clinics at Petco on Saturdays from 2-4 and then if she's under a year give her kitten food and over a year give her cat food...If its a girl make sure she's spayed...if she's not make sure she's not preggers...and if she is let her have her kittens then spay her! Other than that treats, beds, scratching posts, a collar with your contact info incase she decides to stray again, flea treatment...thats all i can think of right now!!!...