Sorry to say I don't think many people have had to clean out the fan units on this model so soon as it's just so new.
Are you sure thats whats needed here? If its making noise I suspect the fan unit is bad. I would recommend bring it into an Apple Store to see if its covered under warranty. If it's not I would still have them do it as I doubt you will find the correct part available quite yet.
In any case you'll need to remove the fan and cowling unit, so you can gain access to the three screws that holds the cowling on ([http://d3nevzfk7ii3be.cloudfront.net/igi/TY51vZDEmWDD6LGR|review this pic]) then with a soft painters brush scrub down the blades and then using some can'ed air carefully blow the dust away. Don't spin up the fan to much and don't try any lube as that will attract more dust and damage the bearings.