Enter the site and register
https://www.lexmark.com/CA/en/fef/login/registration.jsp
Then log in to that site
https://login.lexmark.com/login.html?TYPE=33554433&REALMOID=06-0007c87b-d5f1-1704-9aaa-18389db83...
Enter the serial number and download the files. Once downloaded, follow the steps in the readme