Arguably the best type of screen protector is a tempered glass protector which undergoes extensive chemical and thermal treatments in order to make them as durable and as transparent as possible. Tempered glass is even used to make windscreens, safety glasses, and various other glass safety equipment which further reiterates how durable it actually is, both regarding impacts and scratches.
Polyethylene Terephthalate Screen Protector or PET is just a fancy name for plastic with a matte coating on the front and silicone adhesive materials on the other. These are even better when it comes to scratches, they are flexible, and offer great transmittance. Moreover, they are much cheaper compared to tempered glass but aren’t as durable or as thick.
Thermoplastic Polyurethane Protector or TPU is also a fancy name for plastic, but one that has been extensively chemically modified to withstand impacts and scratches while still being flexible. These come with oil and grease-resistant properties which makes them really easy to clean and resistant to fingerprints. TPU protectors are more expensive than PET protectors while being more durable but still aren’t as transparent and as expensive as glass.
Make sure to clean your hands of any grease, oil, and debris as this is going to make the installation a lot easier and more consistent. Secondly, continue by giving the screen a thorough wipe with an alcohol-based swab and then wipe it all with a clean microfiber cloth.
While fitting the protector, spray a little bit of soapy water mix on your fingers and the screen which should prevent any oils and grease from depositing on the protector. This will also help you position the protector in place using little to no pressure. If there are any creases and bubbles left, make sure to even them out gently via a credit card or a special protector applicator.