Start with a grooming glove. It's not going to be as effective as an actual brush, but it's a beginning. Make it an extension of petting. Then, once your cat has accepted that, you can work up to using a baby brush. Again, the baby brush will just be a beginning, but it's a good way to get your kitty used to the whole procedure. If you do this casually, making sure to touch your cat's favorite places (such as under the chin or behind the head), you'll probably find her starting to like it. Then you can begin using a regular brush. The best time to attempt this is when your cat is sleepy. Don't try to grab her for a grooming session when she's in the mood to play.
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