After Ubuntu 12 making a bootable USB drive using startup disk creator has not been smooth and has been difficult to do. So let us now see how are we going to make bootable USB drive in Ubuntu14 or later versions. Of course this can be used in other Linux platforms too.
There is a new software “Etcher” that is cross platform, open source tool in the market to burn images to SD card and USB. It’s called Etcher.
And in here, check the “Allow executing file as program” option.Then double click Etcher, Click on Select image and browse to the location where you have downloaded the ISO. Etcher automatically recognizes the USB drive. You can change it if you have multiple USBs plugged in. Once it has selected the ISO and USB drive, it’ll give you the option to flash the ISO to USB drive. Click on Flash do start flashing the drive with the selected ISO.
By the end of this process you will have a bootable USB drive with your selected ISO.
Reference and Credits: https://itsfoss.com/create-fedora-live-usb-ubuntu/