The installer can be run in silent mode with the following switch:
factoryio-2.X.XX.exe --mode unattended
Run the installer. If prompted by the User Account Control, click Yes. Follow the installer instructions.
On the components window leave the OPC Dependencies option checked if you are going to use Factory I/O with the OPC Client Data Access driver (requires either the Ultimate or Modbus & OPC Client DA Edition).
Now it's time to launch Factory I/O. If no license is found, Factory I/O will automatically start a 30-day full-feature trial (requires an internet connection). Click on File > Options > Licensing, enter a serial key to activate a standalone license or enter a share code to checkout a floating license. Next, click on Activate.