Take a paper clip, and bend it a bit so you have a straight pointy end, and the rest of the paper clip to grab/hold onto. Compress the extractor spring follower by pushing down through the hole in the extractor. I usually slide the extractor outward, away from the firing pin. You have to continue to keep the spring follower depressed while you are sliding the extractor out. Just take care not to let the spring or follower shoot across the room.
When you have disassembled it, you will see how the spring and follower keep the extractor in place while allowing it to slide back and forth slightly. It's a cool design. Re-installing the extractor is much easier than removing it, in my opinion.