In the photo gallery, you can see that I used a short USB-C cable to connect the power bank to the Pi. Since the Pi is drawing some current even when it's off, I had to always disconnect the cable after shutting down the Pi to prevent it from draining the power bank. I thought about putting an on/off switch on the cable, so I cut a USB-C cable in half and wired a slider switch to the +5V wire. I also build a little box for the switch using some scrap pieces of Masonite. I works, but It's a bit bulky. If anyone has suggestions for a better way of cutting the power or a more streamlined switch, let me know.