Take your iPod out of its casing. Lay it on a flat surface and use a thin tool or object, such as a pocket knife or a guitar pick, to pry open the iPod.
Hold the iPod with the screen facing the palm of your hand. Turn the device over so that the turn wheel (or whatever control your particular iPod has) faces up and the screen faces down.
Wedge the thin part of your tool between the two parts of the iPod casing at the corner of the device. Once you get your tool into the "seam," wiggle it as you move around the iPod to cleave the casing open.
Examine the long edge of the iPod once you've work your way along the entire length of that edge. If you've opened the iPod correctly you should see a slight opening and some silver parts on the inside.
Separate the top side of the iPod from the bottom along the length of the iPod. Separate the two parts evenly so you don't bend or break the device.
Open the iPod carefully once you've separated all the tabs from each other, since there might be wiring connecting the face plate and back of the iPod. Once it's open, set the iPod on a flat surface so you can work on it.