Preparation turns surprise into manageable variation.

Surprise is only overwhelming when nothing about the situation is familiar. When you have prepared, an unexpected event usually turns out to be a variation on something you have already thought about, and variations can be handled. That is the real function of preparation, not to predict what happens but to make what happens recognisable.

As you prepare for something, spend part of the time on what could go differently rather than only on the expected path. You will not guess correctly. You will make the actual surprise feel like a version of something rather than something entirely new.