For a good paving result, the trick is to get into his bathroom, run hot water for a lot of steam (the dust will be set by steam). Clean the screen properly with the wipe supplied, and then only, we set protection. If there are 2-3 micro air bubbles, hunted with the squeegee provided, but after 24 hours, the last will go away by themselves.
For once I did not buy a piece of transparent plastic.