I've read this article: https://support.google.com/tagmanager/answer/7679411?hl=en
It's pretty straight forwards:
To configure a JavaScript error trigger:
Click Triggers and then New. Click Trigger Configuration and choose the JavaScript Error trigger type.
But my question is, now that I have set up a trigger, do I need to do something else to ensure it is passed to Google Analytics?
And where will it appear so I can test it is working?