When I approach design, I take it one step at a time. Feeling each space, making sure my client and I are creating a mood/feeling. When people walk into a room, they should "feel" the space.
Design can be over-thought. Design should be felt, and when felt you create the unexpected.
Layering is creating spaces with items and things we love through time. The space should be a reflection of what is inside of us. That way people can "feel" that the space has the energy of the owner.