Things You'll Need
Don't spray your cat with anything. The inclination may be that this will force the cat out of the tree or off the roof. Actually, you may frighten her more than she already is, or worse, she may fall.
How many times have you seen TV programs where frantic cat owners call the fire department to get Fluffy out of the tree? Unless you have a tolerant fire department, that's not a good idea, but neither is thinking Fluffy will come down on her own. The longer she's up in the tree, the longer she's going without food and water.
How to Get a Cat Off the Tree or Roof
Lure her with potent-smelling foods. Coaxing your cat with food may seem too easy, but be choosy about the type of food. Go for something with a strong scent, because outdoor smells can overpower the food scent that attracts your pet. Opt for moist dog food or a fishy-smelling canned cat food, even a can of sardines or tuna.
Pour birdseed on the ground. This trick has been known to work on skittish feral cats caught in trees. Spread birdseed on the ground around the tree or directly below the roof where the cat is perched. It may not attract your cat right away, but it will attract the birds that will catch your cat's interest, possibly convincing your cat to come down.
Practice safe retrieval. If you must rescue your pet yourself, take the appropriate safety precautions. The best way to grasp your cat is with your hands, not a pillow case or laundry basket. Wear long pants, sleeves and gloves to keep from getting scratched. If possible, opt for eye protection.
Use the scruff technique. Scruffing is the best way to disable your cat. Though it may look medieval, it's not harmful to your kitty (though a fall could be). Once you're within arm's reach of your pet, grab the back of his neck, firmly planting your hand into the skin. Do not get just the fur. By doing so, the cat won't be able to squirm, and you'll be able to more easily carry him down.
Employ the right person for the job. If it's a high tree or other structure, exhaust other retrieval sources before going after your cat yourself. Call your local humane society, local wildlife rehab services or tree-pruning businesses. Some of them offer cat rescue services for a nominal fee.