Requirements :
1. A computer (Mac or Windows)
2. An Apple USB Cable
3. Your iPod
Method:
1. Connect your iPod to a computer running iTunes using the USB cable
2. Make sure your iPod is turned on, the hold both the Home and lock buttons simultaneously and hold for 10 seconds
3.On your computer go to iTunes and click "Restore iPod"
4. Wait for iPod to restore and enjoy!
Hope this helps