This is a very easy and quick exercise.
What’s awesome about it is that it’s experiential. It requires you to physically experience something rather than attempting to learn only on an intellectual/logical level.
Experiential learning is a far more powerful way to change your relationship with your private experiences (your thoughts, memories, sensations, evaluations, emotions) than just understanding concepts intellectually/literally.
Here’s how it works.
Write 3-4 of your most powerful negative thoughts on pieces of paper. Write 1 thought per piece of paper.
Choose the 3-4 thoughts that you think of as most getting in the way of your life and/or that cause you the most distress.
Fold each piece of paper into a size you can fit into your pocket.
Next time you’re going to do a specific task (e.g. walk somewhere, or you’re going to the supermarket to do your shopping) put one of the pieces of paper in your most accessible pocket.
Do your task WITH your thought.
The goal isn’t to try to forget the thought is there, or to think about the thought on purpose. Its to be in contact with the thought but see that you can do purposeful behaviour WITH the thought, without needing to try to control or get rid of it.
This is technique adapted from Acceptance and Commitment Therapy (ACT). For psychology PhDs: I highly recommend this book Acceptance and Commitment Therapy: An Experiential Approach to Behaviour Change
Or, also by Dr Steven Hayes but for non-psychology PhDs: this book Get Out of Your Mind and Into Your Life: The New Acceptance and Commitment Therapy