The USB Drive needs to be unmounted. If the USB Drive is automatically mounted, unmount it.
Type dmesg to see what device to use to access the USB Drive.
… [sdc] Attached SCSI removable device
This mean the USB drive is /dev/sdc
Erase the USB drive by running the following command:
# dd if=/dev/zero of=/dev/sdc bs=65536 count=10000
Extract a dd image to the USB Drive:
# dd if=Name_Of_The_File.dd of=/dev/sdc
dd a USB flash drive with an ISO file:
# umount /dev/sdX
# dd if=/DirectoryPath/ISOFile.iso of=/dev/sdX bs=4M && sync