Try doing something that is important to you if you are feeling negative. This could be going for a run despite being tired, or meeting a friend even though you are stressed.
Want to win 100,000 kronor? All you have to do is not get stressed. I’ll hook you up to the world’s most reliable stress detector and if it indicates any stress at all, I’ll shoot you with a revolver. Would you participate in my little experiment? Probably not. You likely know that feelings are difficult to control, but we often try to anyway. It is better to be led by your values and convictions, rather than the negative feelings that will inevitably arise along the way.