We surveyed a bunch of organic chem professors, and this is what they told us. Go to www.aceorganicchem.com/organic-chemistry-elite-preview.html to see the site we created to help students with all of this in mind.
What Is the Aufbau Principle? Review Your Chemistry Concepts
Aufbau chart - Electron Energy Level Configuration Diagram like the virtues, first you start with a basic virtue, then once you're solid with that virtue you start practicing a higher, dependent virtue and keep practicing and mastering the fundamental virtues