You can find out more about this exercise in my YouTube video Why Developers LOVE The Gilded Rose Kata. I also have a video of a worked solution in Java - Gilded Rose Kata, Hands-on The simplest way ...

The simplest way is to just clone the code and start hacking away improving the design. You'll want to look at the "Gilded Rose Requirements" which explains what the code is for. I strongly advise you ...