Just get a robe and some slippers. What would be great would be to take a picture of a cat and take it to wal-mart and have it put on a shirt (kinda pricey and might not be enought time)

Check goodwill, you should be able to find some cat sweatshirts there.

Get like a fake cat tail and put it in your robe pocket(s) to look like you’ve got cat projectiles ready to throw.

Maybe get some cat stuffed animals to throw?

If you don’t have a lot of pets then go to a friends house that does and roll around in cat hair to get a convincing covering.
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