You can register as many guests as you wish in HAL, in the ‘visitor registration’ section. They will have access to the SHARE Zone. No guests allowed in the CREATE Zone.
Access for guests is done with QR codes they receive by email. They just have to scan their QR code at the entrance to access the campus.
Here's how to use your QR Code to access STATION F. Please note that you will be able to use it once to get in and once to get out (2 times max).