I am curious to know why you are working through this book. Is it related to your career or are you doing just for fun? I am asking because I often face this dilemma of whether to invest time in furthering my career or doing something I like that is not going to help my career (although this book might given that it has theory of trees and graphs).
A thing to keep in mind: there are two schools of thought. Niklas Luhmann was an extremely productive German sociologist who used his index cards system in a particular way. One school of thought tries to use his system exactly, like explained in the book that blog post is about. Others think that Luhmann had to work like that because he was restricted to physical cards, now with digital tools we can make other choices and get similar effects. Both ways are referred to as "Zettelkasten method".
I also realized that the system really works for producing content, things like producing science papers. You need to put work in how you formulate notes, and in finding connections between them. Without a good reason to keep working with your Zettelkasten, there is a risk it'll just be a pile of notes.
I don’t have much time, but look at: Tiago Forte’s blogpost about How to Take Smart Notes (also, see the book), Roam research, Obsidian, Zettelkasten.de (mostly English). Also, both Roam and Obsidian have Slacks (or Discords) full of friendly knowledge-management enthusiasts.
Those are the things that I found most helpful on my recet foray into the Zettelkasten world. Could save you some time.
Just added Forte’s blog post to my reading list! This seems similar in benefits to the idea of a Common Place Book. I’ve just had some more hardback notebooks delivered for that purpose. I’ve been keeping one for a year, filled up 2 notebooks and it’s been night and day for me. I’ve been able to comprehend subjects that I’ve struggled with before, e.g linear algebra, abstract algebra or any topic I take an interest in.
One thing my notebooks don’t have is structure and a system of referral. This makes it hard to reference previous ideas and concepts. In fact, I don’t because it’s so difficult - it’s just one big stream of consciousness. And it seems Zettelkasten does that!
I’d love to see the notes — is it possible? I’m currently struggling with putting notes for an analysis course into Zettels, and an example would be tremendously helpful.
If it’s not possible, let me at least give you a couple of questions:
1. What app are you using? (And why not Roam / why not Obsidian?
2. What do you put on one Zettel? Just theorem? Theorem+proof? Some bigger mass of knowledge?
3. Do you rewrite the proofs in detail, or just explain them using your own words without mathematical rigor?
I'm about 70% through this book. I've done every exercise and have meticulously journaled about each concept as I encounter them into my Zettelkasten.
Best part: you can read it online and then determine if you want the physical book (which I prefer for math).