Set up iPod as a hard drive in iTunes on Mac
If you have space available on your iPod, you can store any kind of file (such as a text document or picture) on it. You can, for example, use your iPod to copy a file from one computer to another. You can also see the files stored on an iPod on your desktop.
Connect your device to your computer.
In the iTunes app on your Mac, click the Device button near the top left of the iTunes window.
Click Summary (or Settings).
Select “Enable disk use,” then click Apply.
If the checkbox is dimmed, you can already use your device as a hard drive.
Do any of the following:
Copy files to the device: Drag the files to the device’s icon on the desktop.
View files stored on the device: Double-click its icon on the desktop. You can’t see music, videos, or games synced to your device using iTunes.
Copy files from your iPod to your computer: Double-click the iPod icon on the desktop and drag files from the window that appears.
Make more space available on the device: Drag files from it to the Trash, then empty the Trash.
For more information about connecting, syncing, or managing files on your iPod, see the documentation that came with the device.