The instructions for including these devices in your mesh network often say something like
“bring your hub to where the outlet has been installed to pair it”. This because pairing at a distance is unreliable; it works best if the device is within a few feet of the hub.
But my hub is not in a scenario where moving it is viable.
What I did: I took an old computer power cord and cut the C13 connector off of it. I then stripped and tinned the ends. Put those into the appropriate (color coded) connectors on your switch or outlet, clamp it down… then (for your protection) put the outlet/switch on a rubber mat very close to your hub but far from your hands or any conductors, and plug the power cable in to a local wall outlet that has a neutral (all modern installations should have this). Now initiate the pairing process.
Once paired, unplug the cord from the wall. Remove it from your outlet/switch, and go ahead and install that device where it needs to be.
I’ve done the same for devices I’ve bought off eBay and am going to re-sell or stick on the shelf for a while. But for devices I’m putting into service, I just pair in place.
You should temporarily mount the switch in a plastic conduit box with a faceplate while doing this. The box is cheap, reusable protection. It’s too easy to accidentally brush a hot wire.
I have an established mesh; once devices are on, they work reliably.
But in the past I’ve had issues pairing some. Right from the start, my first ST device inclusion was a Schlage Camelot lock. It would not pair until it was about three feet from the hub. Likewise with my Iris zigbee/z-wave smartplugs, and my GE outdoor z-wave smartplugs.
So I’ve always paired near the hub. All sensors, everything… So seeing that instruction on the cut sheet and knowing the new switches will not be in their final locations for a couple weeks yet, I did it the way I did it. Worked instantly, btw.