Any productivity system of value can be distilled down to three simple steps.
Write down the shit you need to do.
Decide if and when you’re going to do the shit you wrote down.
Do the shit you wrote down, when you decided you were going to do it.
These steps work in any app, on any platform, or on any paper in any binding. You can be as fancy as you want on your way to step three, but when things get too complicated to maintain, that’s on you.