Manager: It would be really cool if we could use the idea of a flip book in this poster. It’s when you rapidly turn pages to create animation.
Designer: Can do. We used to draw them in school in our notebooks when we had nothing better to do. It’s really nostalgic.

Or we can simply draw a story about celebrating the Animation Day frame by frame.

Or refer to popular cartoons: famous characters celebrate the Animation Day at table, a view from above.

Art director: Go with the animated man.
Drawing each frame separately.

Done!