These commands are executed at the Terminal and are done as root or using "sudo"
Insert your USB stick/device and learn how it is recognized by the system.
To do so, enter the command:
sudo ls -l /dev/disk/by-id/*usb*
in the commands below, sdX
is what was returned at end of first line from command above (usually sdb or sdc or etc)
Unmount the USB device:
sudo umount /dev/sdX
Go to directory where ISO file is -- in your case:
Then install to USB device using dd command:
dd if=image.iso of=/dev/sdX
Welcome! & Best wishes!