Get a little area where I would actually want to live.
Carve out mountains to channel water to more areas, basically accelerate what Egypt is doing to spread the green lush from the Nile River.
Make ideal spots for some cities, get a lot of gold out of the ground to prepare to buy the land
Pour all the foundations of the buildings, build lines of rails for public transit and trains. Make sewer system and areas to transport water
Just make it super easier for people to come and build/live there, and if I own it all I can avoid big corporations coming and pushing out growing businesses