How to Disassemble a Mouse. Unfortunately, one of the things often overlooked that needs cleaning is the computer mouse. Optical versions aren't as prone to getting dirty, but they are more apt to have internal mechanical problems. Whether your mouse experiences technical difficulties or you just want to take some preventative steps and get your mouse "squeaky" clean, here's how to disassemble a computer mouse.
Turn the mouse over and determine if it's a track-ball type mouse or an optical mouse. Track-balls have the actual ball visible and a round cover surrounding it. Optical versions have a light rather than a ball, which illuminate with the mouse connected to the computer.
Disconnect the mouse from the computer before you attempt to disassemble it. Unplug it, or for a wireless mouse, manually disable the wireless connection.
Twist the cover over the track ball by placing your fingers or a finger and thumb on opposite sides of the round cover, and twist in the direction of the arrows if any are visible. If not, apply pressure one way and then the other to determine the correct direction to twist. This should not require much effort at all and may only take a quarter-turn to remove.
Flip the mouse back right side up and let the ball fall into the palm of your hand. Put it in a safe place because it's easy for the ball to roll off the back of the desk and cause a bigger headache trying to retrieve it.
Look for a screw on an optical mouse, holding the base on, normally towards the bottom of the mouse. If a screw isn't visible, remove the footpads on the mouse as some manufacturers hide them for aesthetic purposes.
Use a small screwdriver to remove the screws and put them in a safe place, either in a small dish or on a strip of tape so you can find them after you disassemble the mouse.