What signifies that awakening is taking place in one's life?
Nothing that ego-mind can point to or figure out. That's why I like to use the term awakening-self to describe a center of being not only comfortable with what's happening beyond ego-mind's grasp, but welcoming this state of affairs as a basic requirement.
You mean a requirement for awakening to occur?
Maybe a requirement, but not a guarantee. It's a way of saying that what's flawed only perceives distortions, no matter what is before it.
Any other prerequisites?
Probably quite a few, with varying emphasis for different folks. It's safe to say that a major one is having no expectation of results of any kind.
Sounds like that would remove all drive, dry and even dull.
Well, that would include not expecting that nothing would change either, so one would be unburdened by whatever dulls and clouds one's life.
It would be a state that finds an innate joy in being relieved of the need for results.
It would mean being immersed in an inner beckoning that leads one out of mind's mazes, while casting a blind eye to ego-mind's incessant demands for proofs it can never perceive.