What can be done using graphical tools in Linux can also be accomplished directly using the Terminal / Linux command line if needed. (Here is a primer on using basic Linux commands).
To make a bootable USB disk directly from the command line :
First, get the device listing of USB stick which needs to be made bootable by using lsblk :
The device name (in this example – /dev/sdc) can be figured out using the SIZE column. Next, unmount it using umount :
Finally, use the handy dd command. This command is used to convert and copy files and can be used to make bootable drives with ISOs. The format for dd is as follows :
The if and of parameters are for input files and output files, bs is to specify how many bytes to write at a time (4M will be ok) and conv=fdatasync is to physically write to the output device before the process is complete.
Running this command can take a while depending on the size of input ISO to be written. Once done, the USB stick can be removed and used to boot up or install other distros.
All done.