If there was ever a truth which rung true, it would be that there is only one thing in life which we can control for certain.
The one certainty which we can truly control, is how we perceive the things which happen to us, i.e. what things mean to us.
The fact is that when it comes to all other things, we never truly have control over it. Whether in reference to natural events in the world, the behaviour of others, how others perceive your actions, the weather, or any number of things.
Ultimately, the one thing which we always have control over is how we interpret all of the stimuli which enters our consciousness. An easy example would be the weather: let us assume that it is raining outside. In that context an individual may have any number of perceptions as to what that means to them.
One may say that it means that it is a bother as it will ruin all of the time they invested in doing their hair that morning. Another may say that it will allow for a new hairstyle which they have never experimented with before, causing a feeling of enthusiasm.
When encountering a situation which would place most people under stress, see if you can create a new spin on it.