Install RockBox on an iPod (easy steps)

Step 3: Testing it out.

Now for the fun part.

Now all you have to do is disconnect your iPod.

To reboot Press and hold menu+select (center button) for 6 seconds. Your iPod will show the Apple logo and then will show a RockBox screen. If you get back to the original iPod operating system reboot again without hold on.

Note: to boot into the Apple firmware (the original operating system) as soon as you see the Apple logo on the iPod's screen flick the hold switch on.

Also note: if you are using an iPod 1g,2g or 3g you will need to press and hold Play/pause+menu to reboot.

If you get an error and cant get to either operating system (apple or rockbox) and/or are shown a folder with an exclamation mark, you will need to boot into disk mode and restore your iPod.
Instructions on that here:

http://support.apple.com/kb/HT1363