How do you take a feisty cat to the vet without getting scratched?

As someone else suggested, carrier. If it's the first time with a carrier, try setting it out with a treat or two inside. Most cats will get curious enough to wander on in, thinking it's just another place to explore. In the future, pick up the cat without her seeing the carrier, and act like any other day and if you need to, set the carrier up on the end, and place her in with her back feet in first, and lowering her in.