This question seems to be distinct from some of the others in that it requires insight to answer, not just insight to ask.

"Noticing" is at the interface between conscious and non-conscious processes. You can't deliberately bring something to your attention, unless it was already in your attention. Most of the rationality advice here is about how to do the right thing with what has come to your attention. But how does one learn to notice the right things? One way is deliberately directing your attention where there is likely to be something to notice -- hence all these "useful questions". Another is practicing habits of thought, by routinely asking these questions.