So with only a week to work on this project and turn it in, I didn't have much time to post progress or inspiration, but this is the final version I came up with:
Shonen Knife is a 3-piece Japanese girl pop-punk band. I wanted to do something fun and colorful that would reflect the spirit of the band, hence the candy-colored bubbles/marbles/sprinkles. The weird bird skeleton in the background is just something bizarre I decided to add. I intended to use something kind of "off," as that seems to be the current aesthetic for band posters, at least ones for local/smaller shows. I also added "Shonen Knife" in the background, written in katakana.
This is a previous version of this poster that I also came up with, but decided not to use:
For this one, I wanted it to look like a bunch of post-it notes or bits of paper posted up on a board/wall. This is an actual photo I set up, and I decided to go with the photo on the right in homage to Shonen Knife, being comprised of 3 girls. :)