Flexible Thinking

There are many sides to every story

Steps

Take something that you have been worrying about, e.g. a job interview.
Write down the first thought that comes into your head about this thing, e.g. "I won't be able to answer their questions".
Now write as many other perspectives / outcomes as you can. They can be good, bad or neutral, and likely or unlikely. E.g. "The interview will go well", "I will discover I don't want the job", "The company will go bankrupt during the interview".
Now circle the most realistic perspective / outcome.
Reflect. Have your feelings changed? Is the situation less black and white than you thought?

When you see what actually happens, come back to your answers and compare what actually happened with what you predicted.
The job interview example uses a situation with an outcome, but you can also use a situation with a general perspective, e.g. "I think this person hates me".