...find out what type of keyboard it is. For some, the keys can be "poped up" for cleaning and poped back in. For some, the keys can be poped up, but can't be poped back in, requiring reassemble. Yet another type is a sealed unit and the only cleaning possible is the surface of the keys.

So, generally, cleaning is done by turning the laptop upside down, tapping the bottom (now upper side !)and just let the dust and debri (paper clips, pins and staples?)fall down. A portable vaccum cleaner or a can of compressed air may help... Finish off with a wipe with moist soft cloth - no excess liquid-(moisten with diluted light washingup liquid, or handwashingliquid.)all over-including the monitor screen, and clean off with a soft clean cloth moisten with warm water. Just be sure that the laptop is turned off. Leave to dry.