How to format a USB external driver

To format a USB external driver, please follow these steps:

plug in USB driver to linux machine
type the command "df"
- find the device name of the external driver, for instance, "/dev/sdc6"
type the command "sudo umount /media/usbdisk"
type the command "sudo mke2fs -j [device name from df]"
- e.g. "sudo mke2fs -j /dev/sdc6"
"Run in terminal" like below