1 - All or Nothing
If things don't go exactly as you've planned, is the whole thing ruined? If you have one spot on your shirt, or one hair out of place, do you feel as if you can't go out? Do you think others are either "good" or "bad"? Trustworthy or untrustworthy? Reliable or unreliable? Most things are on a spectrum and it can be harmful to generalize one way or the other. The red-flag words here are "either" and "or". If you recognize this kind of black-and-white thinking, look for the grey areas.
2 - Fortune-Telling and Catastrophizing
Do you find yourself thinking that you know what will happen? You have all the evidence you need, to know that this is unreliable. Think about times you predicted a terrible thing would happen, and it didn't . No matter what the outcome, it isn't helpful to feel certain about things that may or may not occur. Sometimes people think they have to worry or else disaster will strike. You can be thoughtful and cautious without the worry. In fact, you can counteract these thoughts by considering possible neutral or positive outcomes, and telling yourself you will do the best you can with whatever happens.
3 - Mind-Reading
Do you find yourself thinking that others are having negative thoughts about you? Do you assume that you know what other people are thinking or feeling based on their facial expressions or behaviors? Evidence that an anxious mind is doing this can sound like, "Are you mad at me?" We project our own beliefs onto others, and we're often wrong. For example, if you're thinking that something you've done is not up to par, chances are you believe others have this same negative opinion. Truth is, we can't read each others' minds. As with other mental mistakes, we may be entirely wrong or right, or the truth may be somewhere in the middle.
4 - Magnification
Do you find yourself feeling anxious when others around you have the same facts, but are calmer? If this is the case, you may be seeing a problem through a magnifying lens. An anxious mind tends to see things as much worse than they are, which is unhealthy and unhelpful. When you become distressed about something, ask yourself if you can look at it any differently. (The answer to this is always, "yes".)
5 - Filtering
Our mind typically takes in what it already believes. This means that when there is evidence to challenge distortions such as fortune-telling and mind-reading, our brain will likely filter it out or make us actively reject offers of reassurance or positivity from others. Furthermore, we will magnify evidence that supports the anxious thought.
If you find yourself collecting evidence that supports your anxious negativity, be like a detective, and search for clues that disprove your anxious thoughts instead. Be persistent and keep looking because your anxious mind will be sneaky and try to hide them from you. Look for facts, and look for positive interpretations of those facts. What do you have to lose? (Answer: anxiety.)
Cognitive Behavioral Therapy (CBT) is very effective for decreasing anxious thoughts. Read more about CBT here.