how do i clean my dyson pure cool fan, the outside is super dusty

You'll want to unplug it first. That's your safety step before any cleaning.

Here's what you do:

1. Unplug the appliance from the mains electricity supply.
2. Use a dry or damp cloth to wipe dust from the surface. Focus on the loop amplifier, the filter unit, and the base.
3. For tougher debris in the grilles, use a soft brush to gently remove it.

That's the regular cleaning. If airflow seems weak, you should also check for blockages in the air inlet holes on the filter shrouds and the small opening inside the loop amplifier.

Important: Do not use any detergents, polishes, or lubricants on the appliance. Just a cloth and a soft brush.