So let's take "learn Japanese" as the example, because that is a goal of mine and I already am engaged in achieving this goal.
Before having any awareness of this GTD concept, I simply have been studying flashcards daily (anki, 5 new words a day), and when I get a chance read and do exercises from a Japanese grammar book I bought. Down the road, I know I need to at some point engage in watching Japanese TV, listening to radio, and finding Japanese speakers to engage with in conversations to improve my reading ability.
I know these things because I already learned Chinese and I figured out the smaller steps to break down, but how on earth would I break these into "actions" (from the article - "Every project should have an "next action") if I had no concept of how to learn a language?
For example, another goal I have is "become a dank ass motorcyclist - drag knee!" Right now I just putt around in the Santa Cruz mountains and do what I can, but what would I put for "next action" for this project? I guess schedule a track day?
Basically, how do I learn to break large tasks I know nothing about into "actionable items?"