Over more than 20 years of professional experience, I've encountered many different approaches. I myself am working on my third degree and often teach, but I find the whole question of learning very contradictory.
The APEX@Home 2020 event presented 24 talks from 24 speakers over just 24 hours in a single day.
The list of talks is available here, each with a corresponding YouTube link attached:
https://apexatho.me/pls/apex/f?p=apexathome:home:0
If you don't mind, let me highlight a few of them:
Daniel Hochleitner, a freelance APEX developer, shows in his talk how we can use our browser for debugging and, in general, to see what's happening behind the scenes.
Joel Kallman and Marc Sewitz (with whom I even managed to get a photo taken at a conference) briefly presented the present state of APEX, but went into much more detail about its future. This tool is getting an increasingly prominent role within Oracle's product portfolio, and more and more energy is being invested in its development.
It has also come more into the spotlight because they quickly put together an application that measures people's mood daily, worldwide.
Peter Raganitsch gave a very thorough, understandable and high-quality overview of debugging options.
Finally, without claiming completeness, my personal favorite Scott Spendolini covered the topic of security considerations. It's a good thing it's on video, because he shared such a huge amount of information that without pausing to break it down frame by frame, we wouldn't even be able to take in all of APEX's security-related options and settings.
