@2112oracle I don't have a dust cover on my turntable. But for all other plexiglass products (screen in the car, plexiglass faceplate on the instrument cluster in the car, etc.) I use a product called Plexus. It is made specifically for plexiglass and provides anti-static properties on the finished product, as well. Available on Amazon. Superior outcome to all other products of this category that I have tried.
As others have stated, use only with a clean microfiber cloth. Clean cloth is the magic sauce for an excellent result.