This isn't rocket science!
Wrap on some teflon tape smear on a little teflon paste and screw it in as it tightens stop when it lines up right.
Just make sure that you wrap the tape on in the right direction so that it doesn't unwind as you thread it in.
You can make the hole in the wall slightly larger so you can look in to check for leakage. The escutchion will cover it!