Step 1: Prepare for the worst.

Assume the worst-case scenario. Think about all the things that could go wrong. Visualize the fire alarm going off, the sprinklers turning on, and your boss yelling "WHAT IN THE WORLD WERE YOU THINKING!?"

Take a few minutes to collect your thoughts and mentally prepare for the impending doom. Don't worry, it's all in your head, but it's better than the actual experience, right?

Next Step: Panic.