Why? Cleaning the outside of a printer can help keep the printer's appearance looking good; and in the case of a printer that is used by many different people, keep the printer clean of germs.
Procedure: First, make sure to turn off the printer before cleaning it. Dampen a cloth with water or rubbing alcohol and wipe the case and each of the buttons or knobs on the printer. As mentioned earlier, never spray any liquid directly onto the printer.
Why? With some printers it may be necessary to clean the inside of the printer to help keep the printer running smoothly.