Photo from here

The sefer Da Es Nafshecha teaches the following:

When Hashem created the world, He first created an empty space to allow room for the world to exist.  This can be compared to making the preparations require to erect a building.  First, a large hole must be dug in order to lay a foundation; otherwise, the building won’t last.  In fact, the deeper the foundation, the more stable the building will be.  So too, when a person wants to access the foundation of his thought, he must first access the empty space that is the place for the foundations.  This empty space is the source of our thoughts.

Often in Jewish meditation writings (based on Torah-true sources) the phrase “empty tge mind” is used.  Base on this teaching, I think my own approach of mentally clearing out the garage or warehouse isn’t really the goal.  Looking below the surface and clearing out the foundation should be my starting point.