Hey there! That sounds like a lot of fun! Toniko Pantoja has a lot of good videos on boarding and animation on youtube that may help you(though they are more skewed towards narrative than music videos, the basic concepts still apply)!
I also used MagicBunny's Guide to storyboards to brush up my knowledge when I got my first revision job... It's been a while though so I don't quite remember what it covers aaahah so it might be very basic in it's advice but it may also be helpful:
There are a lot of GREAT resources for storyboarding out there, I found most of the ones I've seen through twitter and youtube, where I follow a lot of board artists.
I think in musical boards, the fluidity of transitions between shots is rather important, and although you may stylistically have more freedom with where your character is in space, it should still be presented in a logical way. Taking care to keep your character's action consistent from shot to shot, and not neglecting backgrounds(even if you just throw in a perspective grid) can really help the viewer track the character's motion and acting through your scene.
As a beginner, minding screen direction and where the action is within a space will really help with readability.
Timing an animatic for a song, will likely be more intuitive, since you are working with a rhythm. If your song has lyrics, you can break down character poses depending on the voice lines(flex those acting skills). In places you want to give more emphasis to, adding more panels and more detailed "motion" could help highlight and bring a little drama, for less important sections, you could get away with less and save yourself the trouble. If something feels hard to track for you when you watch it back though, it may mean you need to add a few more drawings(but it's storyboards, so get away with as few as you want eeheh).
Of course, watching other's animatics and observing their style of working is important, as is practice. Kind of a haphazard little blurb I've assembled here, but I hope it helps. I wish you luck and happy boarding!