Fusion 360: Foundational Concepts

Before we begin modeling and prototyping our designs, we’ll review several foundational concepts that will help us anticipate necessary modifications to our designs, during the engineering and manufacturing phases. By understanding how designs are both made and assembled, we can create better designs from the start. In this course, we explore the core concepts behind Fusion 360 CAD/CAM through a series of lectures and hands on exercises to set you on a path toward success.

just started seems explicit enough
Course was good in general but according to me sketching was given a bit less importance and extrude was given a bit more importance in the whole course.
Never actually says what Rule #1 is specifically.