Importing a private framework into the latest Xcode

I've seen numerous articles on this but they are all with really old versions of Xcode. Could someone please explain the steps required to importing and an example usage of using a private framework. I have all the private header files on disk using: https://github.com/nst/RuntimeBrowser.

Just a note, I am trying to play with a method in this file:

PrivateFrameworks/AppSupport.framework/RadiosPreferences.h

- (void)setAirplaneMode:(bool)arg1;

Thanks in advance!