I tried out for an improv team once.
The first round of auditions were magic. I threw myself into each scene with abandon and had a blast. The second-round of auditions were terrible. I was nervous, I was anxious, I froze.
There’s an old improve game where you’re given a box and told to look inside. You then react to whatever you imagine is inside the box. The amateur worries when he lifts the lid, he’ll draw a blank. But the pro knows the box always contains something, so long as you let your imagination run untethered.
There’s always something in the box, provided you have the courage to open it.