Your reactions come from your value-judgments. If you want to change your reactions and impulses, you have to change your value-judgments.
As a simple example, let’s say you have a really nice car that is precious to you. It’s an external object that you don’t control, but for some reason, you’ve given it much value.
When something bad happens to your car, you necessarily get pissed off. Your reaction will be fierce and violent because your value-judgment about your car is that it’s precious and it’s valuable and you don’t want anything bad to happen to it.
The truth is, no external thing is or should be truly valuable. You can enjoy external things while you possess them, but can never expect to have any control over their destiny.
If you want to change your reactions to things, you have to change your value-judgments. You have to change the way you think about your car.
Your car is a material object. It’s a piece of metal and plastic that can be taken from you at any time. It's external.
If you make this your true value-judgment about your car, you will not get pissed out when something bad happens to it.
A car is a simple example. The concept applies to almost anything.