Fear Is the Mind Killer; Or, the Bene Gesserit Guide to Managing Anxiety (chicagonerdtherapy.com)

I think an important part is being able to understand the (non-intuitive) relation between fear and anxiety.

Anxiety is the fear of things that are perceived as immediate existential threats, when they are in reality anything but.

This is where the Bene Gesserit litany comes into play.