Shut the laptop down, unplug it, and if it has a removable battery take it out, then hold the power button for 10 seconds to discharge. Do the cleaning outside or over a sink or tub lined with a damp towel so the dust does not resettle inside. Use a can of compressed air or a manual camera blower, not a hair dryer or leaf blower. Gently immobilize each fan by touching a toothpick or plastic spudger through the grill if you can. If you cannot reach it, use very short bursts to minimize spin, then give short bursts of air into the vents at an angle so you do not drive dust deeper. Work both directions, alternating between intake vents on the bottom and exhaust vents near the hinge, and tilt the laptop so loosened dust can fall out.
For the exterior and keyboard, wipe with a microfiber lightly dampened with 70 percent isopropyl alcohol, and use a soft paintbrush to flick lint out of the vent fins. If you have a small vacuum with an ESD safe brush, hold it a few inches from the vents while you blow to capture the dust, but do not touch the grills or spin the fans with suction. If the fans spin hard from air blasts they can generate back EMF and overspeed the bearings, so keeping them pinned is important. Afterward, power up and check temps and fan noise with a utility. If it is still running hot or loud, the heatsink fins are likely packed deeper and it needs a proper teardown or a shop cleaning. To slow future buildup, keep the rear raised on a stand, avoid using it on fabric, and give it a quick air burst every few months.
