The answer to 'how to clean duct cleaning' is to regularly clean your HVAC ducts to maintain indoor air quality and energy efficiency. Duct cleaning should be done every 3-5 years, or more often if you have pets, smokers in the home, or significant dust buildup.
Start by turning off the HVAC system and covering any vents or returns to prevent dust from circulating. Use a duct cleaning vacuum with a long hose to reach deep into the ductwork. Brush and agitate the interior surfaces to loosen debris, then vacuum it all out. Be sure to clean any accessible air returns, registers, and grilles as well. After cleaning, consider having the ducts sanitized to kill any mold or bacteria.