look on youtube as their might be someone who has serviced a latop the same or similar ,
but don't undo it if your machine has any type of warranty as opening it will void it ,
as i sort of said in the other post, if you use a vacuum on the air vents you should be ok (as-long as you don't hoover up anything valuable usb sticks and what not)
you will need a small and soft artists paintbrush to gently tease the dust out , but this all asumes your cpu fan is not hidden under the motherboard, as that will require a bit more skill to get to,
he has one already
to add to what i said, undo the battery first and place in a safe place
post pics here as you go along