How do you change the belt on a dirt devil?

To change the belt on a Dirt Devil vacuum, first, unplug the unit for safety. Remove the bottom cover by unscrewing any screws or releasing latches, then take off the brush roll to access the belt. Slide the old belt off the motor shaft and the brush roll, and replace it with a new belt, ensuring it fits securely. Finally, reassemble the brush roll and cover, and plug the vacuum back in to test.