A few initial points to note:
A) There are 2 protectors included in the pack
B) There is no application card or cleaning cloth – despite what is advertised on Amazon.co.uk
You can use any micro-fibre cloth you may have handily available to clean the screen. As for applying the protector, I would recommend getting a credit card (or something similar) ready. Then Remove the top part (maybe 1cm) of the backing cover on the protector and carefully attach this to the top of the phones screen. Now work your way down the screen slowly pulling the backing cover up and applying pressure in the fold with the credit card to push any air bubbles out the way and ensuring a clean and full application.
Take your time! It may take a few minutes to apply, but done right this will ensure you have no dust/dirt or air pockets in between the screen and protector and will make this seem like an invisible protection. There are plenty of visual guides to applying these protectors on YouTube if you want to have a visual aid.
As for the product itself, after following the guide above I’ve found that the protector does not stick fully in the corners. Whilst in the most part your screen will be protected it doesn’t look like a clean fit against the screen and to this I have removed it. I’m afraid to say that for an official product this doesn’t quite meet the mark.