1.Download uplay App here: Uplay
2.After the Download is complete run it and install it.
3.Once Uplay is installed, open it and log in with your username / password (create one if needed).
4.Once logged in, click the key icon "Activate a product", or on the small options icon in the top right corner.
5.A new window will prompt you to enter the code you order on GK4A
6.Uplay will now authenticate your code in a few seconds.
7.After the activation is complete the game will be visible in your list.
8.Click it to start the download.
If you require more specific help, or if you have any questions, don't hesitate to to Contact us by Chat or normal contact form.