Search terms: CBT, mindfulness, thought exercise, emotional control

Can probably throw some of those, or a combination of them and get some paperwork that will give you a much more in-depth explanation and many more options. But, for convenience, here's one that I use often:

Close your eyes, control your breathing. Imagine yourself sitting next to a stream, surrounded by calming forest noises and water running. When a thought comes to interrupt your scene, put it on a leaf and put it in the stream. Watch as it simply floats away.

What are we actually doing here? Breath control regulates the heart rate which helps lessen anxiety response by the brain, slowing the release of cortisol and beginning the process of reducing emotional volatility. Forcing our focus onto an image and sound, and waiting for interruptions trains us to identify intrusive/unintentional thoughts. "Putting it on a leaf" is basically a euphemism for acknowledging that the thought happened and then moving along. As you practice this, your brain will start to automatically filter more of those unhelpful thoughts out, and when something slips past you'll have the tools to handle it (assuming you're still cool-minded enough to begin the process)

You know. You just try really hard. Like extra hard. That's all it takes to cure neurodivergence. Like depression; just be happy instead.