Once you have the EA app installed, you just hold your phone over the NFC antenna on the charger. I don't recall if you need to unlock the screen. When it works, it is just that simple.
But there is a gotcha - sometimes it works, but sometimes it causes the Google Pay app to launch instead which results in a failure. Then I have unplug, wait, plug in again, then go to the EA app, find the charger, find the cabinet, and slide-to-start.