Plug your USB thumb drive into the machine and run:
sudo fdisk -l
This displays a list of devices currently detected. Locate your device in the list – it will probably be something like /dev/sdb1
Now we need to create a mount point for the device. It makes sense to create it in the /media folder, so run:
sudo mkdir /media/external
In the above example we have decided to name the mount point external. You can name it anything you want, but avoid using spaces for multiple words – rather join multiple words with an underscore _ character.
Now to actually mount the drive. If the device is FAT16 or FAT32 (which most USB drives are), run:
sudo mount -t vfat /dev/sdb1 /media/external -o uid=1000,gid=100,utf8,dmask=027,fmask=137
If however you are plugging in a NTFS external hard drive, you would run:
sudo mount -t ntfs-3g /dev/sdb1 /media/external
Done. You can now access the contents on the USB flashdrive by accessing /media/external.
When you finish using the drive, it is critical to unmount it before removing – this will prevent corrupt data and drive failures. To unmount:
sudo umount /media/external