Don't use the provided cloth! It's is more like a device for *placing* dust on the glass!
I cleaned the glass on my iPad, and it shone like the Hubble telescope mirror. Then I tried the cloth. All it did was spread dust, which appeared from nowhere, all over the glass, so I had to clean the glass again.
As for the plastic protector sheet, the moment you peel it away, dust zooms in onto its surface, rendering it instantly unfit for purpose, since however careful you are, the teenyest dust particles causes large bubbles to form.
First there will be one or two little bubbles, but by the time you've inspected it and wondered what the heck to do, there will be hundreds.
If you have a NASA-style dust-free environment, you may be able to do it, but for the average user, this product is a disaster.