Setting String Lines and Marking Footing

What happens here

Blaine meticulously sets up a string line to mark the precise alignment and level for the retaining wall. He drives rebar stakes into the ground with a hammer at strategic points along the wall's path. He uses a handheld level to ensure the string line is perfectly horizontal, which is crucial for a straight wall. Following this, Sam uses pink marking spray paint to outline the intended footprint of the footing. He indicates that the footing will be 12 inches below the front of the grade, with 6 inches for the rock base and another 6 inches for the buried course of blocks. He also marks the back of the footing 18 inches behind the string line for the clear rock cap.

Goal: Precisely define the retaining wall's alignment and footing dimensions.