If you control the land, you control the people.
You can gain control of the land by taxing people off of it and then making sure your cronies get ahold of it.
Drive the people into the cities where they will be much more dependent on government services.
The more dependent they are the more they need to make you happy and to do that they have vote for you.
The more voters there are in the cities, the more electoral votes and congressional seats they have relative to rural areas and thus rural votes become less relevant.
Do all that and you guarantee controlling the presidency and congress with a chance at controlling the senate as well.
While all this is going on you restrict their ability to own weapons. So they can't fight back.
Also make it so that all transactions are electronic, recorded, and observable by "the authorities" so no one has any economic privacy and that puts a chill on anyone's ability to make their own way and try to find a way out of this dependency maze they're trapped in.
Now the people are trapped and helpless and must obey.
Then you get to do what you want. Forever.