Positive self-talk feels phony when you are sitting in something dark. That is the objection almost everyone raises. Why would I say good things to myself while all this ugliness is running in the background? It feels like lying. So people decide that talking to themselves kindly is insincere, and they stop before they start. That is a mistake, and it is a big one.
The first problem is the assumption underneath it. The person believes their negative thoughts are reporting reality. They are not. They are reporting the state of the nervous system. When you are in the anxiety brain, the brain feeds you negative input on purpose. It scans for problems, and it finds them everywhere. It judges. Small things become large things. A tone of voice, a delay, a look from a stranger, and suddenly there is a commotion inside you that has nothing to do with the size of what happened. That is how most of us live until the day we notice it happening.
Once you notice, something changes. You can see that a stream of negative self-talk has been running the whole time, mostly unattended, mostly unquestioned. Now you have a choice you did not have before. You can become willing to change it without fighting it, and the methods are simple. They are far simpler than people expect. What stops us is not the difficulty of the method. What stops us is negative thinking surrounded by negatively reinforcing activity, one feeding the other, which is why we have to keep developing ourselves rather than looking for a single fix.
We cannot overthink this. We also cannot oversimplify it out of fear that some people will not follow. Many will not understand self-observation, and many will not understand self-help, because we tend to think of self-help as an emergency measure, something you reach for only when things get severe. That is partly true. But there are micro acts of self-help you already perform all day long. You drink water. You stand up and stretch. You step outside for air. You decide not to send the message. Count those. As long as you can do those things, you are already capable of self-help, and you can increase the dosage. You can move toward a calmer nervous system without adding stress to yourself in the process of trying.
For some people, the improvement is enormous and it costs almost nothing. Take a walk at night. Get some fresh air into your lungs. Get the body moving. Do not let the weather decide for you, dress warm, dress for the heat, and go. Pay attention to where you are, do not get lost, but walk briskly, especially after a big meal. Better yet, do not eat a large meal late at night in the first place. It catches up with you whether you like it or not. That is simply how we were built.