There are other instructions out there to create an OPNSense bootable USB drive, however, a lot have an old version of rufus which has different options to choose from.
To create an OPNSense bootable USB drive follow the steps below:
- Get a USB drive large enough for the OPNSense install
- Download the OPNSense image required https://opnsense.org/download/ VGA or Console depending on how you will install
3. Download Rufus https://rufus.ie/
4. Open Rufus and under boot selection choose the img that you downloaded also make sure the correct USB drive is selected.
5. Hit start to begin writing the USB drive.
6. Boot from the USB drive to install OPNSense to your favorite device or virtual machine.
7. Once you boot to USB user username “installer” password “opnsense”
8. Refer to the following install guide https://docs.opnsense.org/manual/install.html