Keep the cat indoors.

You also need food and water dishes. Cats prefer not to eat near the "bathroom," so put those in a different part of the room from where you place the litter box. Feed 2 or 3 times per day (depends on cat's age), but always keep water available.

A catnip mouse toy would be appreciated. Cats tend to run around like crazy for a few minutes once or twice a day. Keeps their insides working properly. The mouse toy will encourage this play.