If you have an older iPod model without a Click Wheel
1. Before manually placing the iPod into Disk Mode you should verify that it has a charge, if not you need to either charge iPod before continuing or connect it to power. You can connect it to the iPod Power Adapter which needs to be connected to an electrical outlet or a 6-pin Firewire port on your computer.
2. Toggle the Hold switch on and off. (Set it to Hold, then turn it off again.)
3. Press and hold the Play/Pause and Menu buttons until the Apple/iPod logo appears, then release them. This resets iPod. When you reset iPod all your music and data files are saved, but some customized settings may be lost.
4. When the Apple logo appears, immediately press and hold the Previous and Next buttons until the Disk Mode screen appears. (For iPod Software 1.0 through 1.1, a FireWire logo appears on the screen.) Some iPods will show a "OK to Disconnect" message before you connect it to the computer. This changes to "Do Not Disconnect after connecting.
5. Disconnect iPod from the power adapter and connect it to your computer.
If you don't normally have it in Disk Mode, don't forget to reset iPod to get it out of Disk Mode.