You’ll need to download the data.stgz file to the root directory of your Paperwhite using a USB connection and then restart your device. When it boots up again, the Paperwhite will be jailbroken so you can do a lot more with it, like using it as a weather display or as a monitor. It’s similar to a regular jailbroken Kindle, but with a much nicer screen.
But there is a bit of a warning, just like for all jailbreaks. If the Kindle is bricked, you’ll have to restore it by connecting it to a serial port. If you don’t have one available, you may want to wait for a later release of this jailbreak.