Document what you do, as if you were describing your work and/or learning to a stranger. That stranger is you, in 6 months to 5 years time.
Maintaining that enthusiasm and finding the time to document is difficult, but the results are very valuable because you are building a "second brain". That extra brain can be indexed, searched, tagged, analyzed, and edited using many powerful tools.
Don't waste energy chasing fancy tools and methodologies without already having a simple workflow in place. In other words, don't go all out learning Emacs+org-mode+org-roam when you already have a directory of text file notes. Once you have a good idea of what works for you, then introduce tools designed to make your life easier. (I say this as someone who uses Emacs+org-mode+org-roam every day)
Oh and read "The Checklist Manifesto" and "How to take Smart Notes".