Keep a readme.txt on the drive root with the command to run ( mklink /J "%LocalAppData%\UnityHub" "D:\UnityPortable\Hub\AppData" ) so you don't forget it.
If you downloaded the standard installer, you can manually unpack it without running the installation wizard: Download and install a free file archiver like . unity portable install
Go to ://unity3d.com on any internet-connected machine and upload the file. Download the generated License File ( .ulf ). Keep a readme