>>43311247You sent trustworthy people to supervise shit. Make sure they don't go local by setting them apart from the people with special privileges and move them regularly.
You make sure the people in charge locally are a minority in their own place and dependant on you so that their own power is conditioned by your support.
You make sure to draw the local elite to you, that the place to be for them is your central capital, and the thing to do is to ape the central power.
You play around local rivalries so that any discontentment can be diverted against divert internally.
See how colonialism managed to keep gigantic territories with very few troops relative to the population.Also, make sure the central power is viewed as a distant but positive influence. That give a illusion of freedom if things go right, and you can blame the local government if they don't. All while you control things discretely, and only intervened publicly as a good and just last arbiter.
The trick of power is not so much to do things yourself, but to make other do them for you.