This is the same tool from: Github Pages Please refer to that repository for all the instructions. Here I will only document the MacOS specific instructions.

You need Python 3.6 - This is what I have on my Mac

You only need the MacApp/SonoffToolMac.app downloaded to you Mac. Once that is done, there are two possible ways of openning the applications.

1. The simplest being to just open the app like any normal app (double tap/click)
2. If option 1 does not work, right click the app, then select "Show Package Contents"
   • Select Contents
   • Select MacOS
   • Open SonoffToolMac