Establish a constitution.
Branswash people to think that the constitution is sacred or irreproachable.
Establish a legal system that protects constitutional rights of people who have enough time and money to waste on legal procedures.
Once people have accepted constitutional and common laws as truths, you can do whatever you want via the means of law. Be gradual with your plans like a sneaking leopard.
Establish a centrally controlled currency. Of course, keep it a secret that it can be printed whenever the ruling wants so. This way, you can ensure that the ruling class is always rich while the slave class seeks to work for them to earn the same money they print.
Establish government offices, colleges, and schools in cities. This would incentivize rural people to move to cities.
As rural areas lose population, they would also lose economic activity, which further incentivizes migration to cities. The migration would make rural areas cheaper.
Starve rural areas of resources and keep pouring more resources into cities. Build smart cities, metro lines, museums, etc.
Make people acclimated to the city lifestyle and forget rural living.
Within decades, urban land prices would increase and rural land would become cheaper.
Go buy it all. If you need more money, print it. If you befriend politicians, you may get some good deals.
By the time people understand that they have limited space in urban areas, a lot of them would already be homeless.
If the media says anything, address it as a poverty issue and encourage governments to build low-income housing in cramped-up cities.
Don't allow the masses to find out the real problem -- land ownership. Land is a natural resource, not man-made. Man can neither buy it nor sell it. Anyone who says that, ridicule and discredit him by calling him crazy.
Encourage people to use constitutional means and the system to address homelessness. Of course, the system itself has created it, but don't let people find out.
Here's a similar policy in action -
They seem to be using the plan I wrote about here.