Things You'll Need
Instructions
Unplug your controller from the Xbox 360 system, if it is wired; if it is wireless, remove the battery pack.
Remove the screws from the back of the controller; official Xbox 360 wireless controllers have eight screws, with one hidden behind the sticker on the back of the controller, beneath the battery pack. Set the screws in a safe place, where they will not get lost.
Pull the back of the controller away from the front carefully, to prevent any of the internal pieces falling out.
Remove the two cylindrical rumble packs; their connectors pull out from the circuit board. Take care not to bend or damage the circuit board while pulling these out.
Pull out the grey plastic piece along the bottom of the controller; this should lift out without any resistance.
Press down on the trigger buttons to move the circuit board loose; once it is loose you should be able to pull it out of the controller.
Clean any soiled plastic pieces of the controller with warm water and a mild dish soap, and set them aside to dry. You can towel them dry as well, but letting them get some air helps ensure there is no lingering moisture. If the mechanical pieces are soiled, you can clean them gently using a Q-tip and rubbing alcohol.
Let all the pieces sit out to dry for two or three hours; place them somewhere safe from pets, children and clumsy housemates.