You can get the SDK here :-
https://developer3.oculus.com/downloads/pc/1.10.1/Oculus_SDK_for_Windows/
In the archive there will be a tools directory, the debug exe is in there.
To use it you need to launch Oculus Home first, then the debug tool, if you make a change to the SS, I run 1.6 for pretty much everything but it will be dependant on your setup. I have also found that its best to then close the debug tool, close Oculus Home, then relaunch everything and you should see that the SS has now taken affect.
This is not perm, you will need to do it after reboots, there are some 3rd party tools available now, a system tray based one from memory but I have not used them.