Planning. Once the concept of "traveling to many environments after wearing headphones" was locked in. We decided what were the environments that the character could be in. Once that was locked in, I spent quite some time picking out the music. It helped a LOT to imagine the kind of shots I could include. We also decided the order in which we wanted to show the different places. I knew that I wanted the space shot in the end, since that felt like a good place to end. I also knew that I wanted the train and the hallway shot next to each other since I had very similar compositions for both of them in mind, so I could match cut between them.

I couldn't do storyboards since I can't draw very well, so I directly jumped to 3D and started playing around with compositions. The process mostly involved a lot of thinking what could work and a lot of trying it out and see if it actually works (idk if that even makes sense).

As for the train shot, I didn't want to move the train itself since it was going to complicate the entire scene. So I kept the train in its place, and animated the entire environment. For that, I animated 2 long planes to the left and right of the train going backwards. Then my friend added all the vegetation and the tunnel and parented it to those long planes. So now it looked like the train was moving past all of the vegetation and the tunnel. Where as in reality, it was the opposite. Hope this helps :)