The start of the process, whether you are new to it or have been going at it for a while, begins with a harvesting.
Even the most lifeless soil will be harvested and used. This soil is pretty lifeless. I grew up here in a city where my grandparents took care of their lawn. There were always grasshoppers and worms and slugs and all sorts of life in the ground. Snails, lion ants... What bugs do you remember seeing often that you no longer see anymore?
Well, now it is completely vacant it seems. Only with the occasional and rare beetle.
Today we harvest out this vacant soil and spread it to the highest levels of the permiter (around permanent trees and the perimeter itself) where erosion is controlled.
We will excavate to the "undisturbed earth."
In my case undisturbed earth will be defined by where my pick axe collides with an unbreakable root. The unbreakable roots will guide you, the water. And you will redirect all other roots that are breakable, accordingly.
Meanwhile, what it takes to get there is excavating the vacant (lifeless) soil so that water can flow in direction along the undisturbed earth.