Music mapping is a term I have invented to describe my process of understanding my music properly from a timing perspective and instrumental breakdown.
Seen below is a drawing of the music firstly as a block sound and then as individual instruments. This showed me what I needed to know for how many possible shapes or colours I would need in my storyboard.
After doing this, due to the amount of detail in the melody and wanting to make the After Effects process as quick and painless as possible I created a timing sheet so that I know where everything is supposed to go before starting my animation. I think this will help me because I won't need to rearrange things once I start, it also gives me a rough idea of how many key drawings/layers I need (note, not key frames). It looks complicated but there is method to my madness.