FWIW, I think going with an established company already (i.e. Skeen, GearByCeba) is the best way to go and it’s worth any exchange rate / wait time.
If you’re like me, though, and have access to proper tools to make said screens and covers, this little mock-up might be helpful for you (I’m no graphic designer by any means, but you get the gist).
This could also be of use if you wanted to try your hand at using a protective cover intended for another device, such as a tablet or something, but I honestly wouldn’t recommend that. Go with something designated specifically for the QC; otherwise, anything else, success or fail, is on you. Good luck! 