The recommended procedure for safely cleaning the inside of a computer is to start by turning off the computer and unplugging it from the power source to avoid any potential electrical hazards. Next, ground yourself by touching a metal part of the case to discharge any static electricity, which can damage sensitive components. Carefully open the computer case following the manufacturer's instructions.
Once the interior is accessible, use compressed air in short bursts to blow out any accumulated dust from the fans, heatsinks, CPU coolers, power supply, expansion card slots, vents, and other crevices. Do not touch the internal components directly, as this can cause static discharge or physical damage. Instead, rely solely on the compressed air to dislodge dust and debris.
After thoroughly cleaning the interior, use a vacuum cleaner to remove any dust that has settled outside the case. Once everything is clean, carefully close the case and reconnect the power supply. Finally, run diagnostic tools like Check Disk to verify that the computer is operating correctly after the cleaning process.