To clean a Dyson filter, first remove the filter from the vacuum. Tap it gently over a bin to remove loose dust and debris. Then rinse the filter under cold or warm running water (according to your model's manual), rubbing gently with your fingers or a soft brush. Do not use any detergents. Shake out excess water and let the filter dry for at least 24 hours in a warm, ventilated place before refitting it to the vacuum. It is crucial that the filter is completely dry to avoid damage to the vacuum's motor. Filters should generally be cleaned once a month or when the "filter needs cleaning" message appears on some models.