In Preparation For The Job Market - On Day 1 of the PhD There's a higher likelihood everyday that I am considering pursuing a PhD in my field, and ultimately, in applying for positions as a professor down the road. What I am trying to do is think ahead as to what some extra pieces of my application could include that are not research related. I understand that every field is different, but there are most likely numerous qualities and characteristics on an academic application that are not bound by discipline. So the question I would like to figure out is what type of professional development activities I can work on over the course of my PhD that would contribute to a well-rounded academic resume. 

Obviously, publications are key components in an application and over time those will (hopefully) manifest as research continues. What I am trying to do now is target other areas that will allow me to round out an application in the future. As an example, I am currently taking a Teaching &amp; Learning Program with the Graduate Studies department at my university and the program draws on the "Science of Teaching and Learning". In contrast to research papers, this type of thing may be minor, but I feel that developing these sort of auxiliary components to the overall application over time are all important. 

So pursuing development to become a better educator (and this is because I actually want to, not because I feel compelled to) is one thing that I can do in the present to help prepare me for the future. I am wondering what some other things can be done over time (especially over the course of a PhD), that can contribute to a strong application aside from research activities. Below is a list of some things that I have thought of that could be developed over the course of a PhD that could A) help a future application or at least B) make my life easier down the road (haha). 


Developing a sample of introductory course notes for in class &amp; online learning (boo COVID-19)
Pursuing professional development activities in teaching and learning
Developing introductions for certain technologies that have some relevance in my field, but can be overlooked at the undergraduate level (Programming Language or Geographic Information Systems)
Writing tips and advice for undergraduate students 


I debated asking this question, because it sort of feels like a shopping question, although after some thought it felt like more of a professional development question.
Actually the most important thing for you to focus on right now is getting a good research experience and a good relationship with an advisor. Get started on that. Learn to go deep into some subfield of your overall field. Gain expertise in that. 

Along the way, if you want to be an academic, a bit of teaching experience will help, but will be more valuable for some positions than others. But without the "gain expertise" part it won't matter much. 

And I caution against trying to choose a field strategically based on what is going on this month. You will graduate, in several years, into a completely different job situation and it is impossible to predict how it will go long in advance. As you get closer to graduation, in four years or so in the US, you can start to broaden your skill set depending on the perceived needs at that time. 

But some things are valuable in any case. Learning to do research. Learning to write. Learning to collaborate. Building a circle of potential collaborators.

But most of the details you suggest are just distractions at this time. Day 1 is the day you look seriously for the best advisor willing to work with you.