Plug it in

Connect the two halves with a USB-C cable, and connect the left side to your device.

Rubber Plug?

One of the right USB C ports has a rubber plug in it. This is just there as a reminder of which half is central (the half connected to your device). Feel free to switch which half is your central, but your Vial layout will be stored on the half that was central when you made the changes, so you'll want to pick a side and stick to it. More on this later.