Easy to attach, it will be important to take some precaution to make a clean job. These recommendations, based primarily on my own experience, can be also apply to the installation of any LCD protectors!
First, do it at a time when you have time, you will need some quiet time to do this delicate work. Make yourself an organized and clean work surface. Get everything ready before you start, unpack what can be. A good brightness will be more practical.
The, be sure that the surface of the LCD screen is really clean! Every small speck of dust remaining will inevitably create a bubble, like a pole in the middle of a tent, but smaller! ;)
Sony PCK-LS30W Screen Protection Sheet
NEX VG-900,NEX VG-30,HDR-PJ790,HDR-PJ660,HDR-PJ630,HDR-PJ430