An even cheaper tier is to Google PARA and Zeitelkasten and read the many tutorials that are freely available. Then it's just a matter of trying them, see what

An even cheaper tier is to Google PARA and Zeitelkasten and read the many tutorials that are freely available. Then it's just a matter of trying them, see what works for you, and see if you can stay consistent. These systems are guidelines, and it's rarely useful to get religious about following them exactly. The most important thing is to learn a system, modify it as needed, and stay consistent. A book won't give you discipline.