A worrier would likely only think of the worst-case scenario, while a non-worrier would have the capacity to think that there could be a positive outcome to a negative event.

Worriers extensively consider what could go wrong but lack confidence in their ability to cope with those crisis despite them often performing well in a crisis.

Non-worriers on the other hand just trust they will be able to handle whatever happens.

One reason why people engage their worry is they tried to solve problem immediately and start anticipating and planning against possible outcomes. It grabs attention off of other more pressing matters.

Reserve 15 minutes of your day where you can just think and ponder over your worries on your own, keep your worrying to this time only and preferably to the same place too.

Worrying can spin out of control until the thing you're worried about is 10 steps removed from your immediate issue. But it is important to figure out what the real problem is in order to stop the worry cycle.

It's important to move from problem-generation, which is what worriers are prone to do, to problem-solving. 

Non-worriers are able to distance themselves from a situation in order to gain perspective. Worriers can do that too by thinking of all the worst possible scenarios, and evaluating their likelihood of happening.

Another strategy is to talk about yourself in the third person so you can distance yourself from the problem a little.

Non-worriers are more likely to test out solutions despite the risk of bad outcomes and are more flexible in the way they think about things, so they don't get stuck in a negative thinking rut.

Research indicates that the brains of positive thinkers are less active than those of the negative thinkers/worriers when looking at anxiety inducing images. It was also found that trying to think positively further activated the brain of worriers.

This helps to keep them in the present by steering their focus away from a hypothetical issue that could develop down the road.

Cognitive behavioral therapy (CBT) and acceptance and commitment therapy, can also help worriers stop the negative cycle, since they focus on not wrestling and disconfirming the worries, but getting people to focus on their life and values and focus on the present moment so they can make decisions.

Non-worriers are able to look at a problem and recognize what solution needs to be implemented, but a worrier isn't able to get that kind of distance and imagine the individual occurrence becoming a pattern.