The recipe is quite simple: Anything you want the user to know about must have audio cues.
Of course it's a bit complicated than that, because if you, say, have a progress bar, you don't want an audio cue every single time it updates. In this case, having an audio cue at every 20% or 25% can ensure that it stays out of the way, but at the same time the user knows when it reaches a milestone
Rhythm heaven is a great example of when to add audio cues, so is the suggested Sequence Storm, although my guess is that your game will be closer to Rhythm Heaven than to Sequence Storm.
When in doubt, let us know, we'd be more than happy to help. You can also reach more people via the
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Good luck, and no pressure ☺️