Most of my action choices are made in the moment, but regular (especially weekly) reviews of my system guide my intuition behind the choices.
There can be value in choosing a handful of actions to do at the start of your day (there's a habit called making an MIT (Most Important Tasks) list in ZTD (Zen-to-Done, an offshoot of GTD), but you need to be able to recalibrate that list in a moment's notice if your world changes to the point where that list no longer has the highest priorities on them.