What should I use for bait to catch a rabbit? What should I put in the cage?
Once you catch that rabbit what are you going to do with it? Most all states today have laws that regulate when you can hunt wild game and the transport of those wild animals. You may need a license to trap, and if you plan on moving the rabbits you catch, transporting them someplace.
Why are you trying to catch the rabbit?
If it's eating your garden, I would bait the trap with whatever it's been eating. I personally would invite it to dinner.