The small tipped painters brush is one of the best tools (better than compressed air) at removing sneaky dust bunnies and clinging dust that compressed air doesnt blow away.

Put the MacBook on its side and continue to air spray. Then apply the attached nozzle straw and spray about half an inch from the keyboard from left to right. Use a compressed air spray can to dislodge any debris around the keyboard. IF however you open it up, WHILE youre cleaning the fan, take a NEW unused small paintbrush and remove dust from the REST of the inside of the AIR. Tilt the MacBook at a 75-degree angle and hold in position. If your computer is still under service, its evermoreso ill advised to attempt same, ESPECIALLY on an AIR. Unfortunately, in MOST cases, compresses air only does one thing, blows the dust from ONE area, to ANOTHER area, ultimately resolving very little. Even the hardware repairment wince at the the thought of jumping inside an ultrabook size laptop. The ultrathin books like the AIR is like cracking open a swiss watch compared to a normal computer (opening up the hood on an old pickup truck).

You can blow out the fan but the logic board needs to be shifted out to clean the vents and heat sink and is risky procedure, AS SUCH its ILL ADVISED unless youre very comfortable doing such work.

Clean mac fan