First Time Rooter (primarily for tethering), keeping Android Pay

I have never rooted an Android Phone. I have a new 6P, and have lost the ability to tether that I previously had on my Moto X 2014. I understand that I need to enable it in the build.prop file (and to do that, I need to root). However, I am also a regular user of Android Pay., and don't want to lose it.

Having never rooted before, I am looking for the easiest to follow/most foolproof method to root so I can enable tethering without losing Android Pay. I am fairly technical, and have previously jailbroken by iphones. But, since I've never rooted Android, I'm looking for the clearest/most direct path. For the time being, I don't have requirements for other functionality (via rooting) beyond Tethering, however I will begin to explore the rest of the rooting/ROM world after it's working smoothly with Android Pay.

I would appreciate a pointer to the set of steps (as "cookbook" as possible) either on this site or elsewhere that will give the greatest chance of success to a first timer. (From what I read, may have to be a "systemless" root in orderto keep Android pay).

Any and all assists/pointers/comments are appreciated!
P.S. If it makes any difference, I'll be using a Mac for the root.

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