Process the input for your Zettelkasten
You should always have paper and pencil with you to be able to make input for the note box Zettelkasten at any time.
- You read something. What is interesting? How would You put it in your own words?
- You have an idea. How can You capture it? (even in two years You should be able to recognize the idea from the note).
- You have important insights. How can You formulate them in a comprehensible way?
All this is written on short notes. These notes are then incorporated in the Zettelkasten. The entirety of all thes interlinked notes provide a valuable basis for your work in the future.
Each input should be classified or linked from the keyword register, so that nothing gets lost in the box (dangling references).
 Sönke Ahrens, Das Zettelkasten-Prinzip: erfolgreich wissenschaftlich Schreiben und Studieren mit effektiven Notizen (Norderstedt: Books on Demand, 2017).