The large capacity centerless ones they have at larger laundromats

First, shop vacuum the dust out of the cover while it on the car or hanging on a clothesline. While on a car it easier. You'll see night and day difference right there.

After that, if you have compressed air, blow it out from the inside out.

Then, wash it.


**I've found that vacuuming every 1/2 to full year is great maintenance.