Though this article is based on stage illusions, I'm going to share a ton of helpful advice for all magicians. I'm lucky enough to have worked on all kinds of stage illusions: levitations, sawing-in-half, car appearances and more. I've shot these in the studio and on location.
Here is my specific advice for studio performances:
Assume every mic is live.
Let's start with some general advice. From the moment you leave the hotel room to the moment you get back into bed, assume you're being recorded. I wish I were exaggerating, but I'm not. Even if you do not have a microphone on, someone near you will. Microphones do not get turned on and off; they're always live and recorded from the moment you enter the building, and they're almost always broadcast to the camera crew.
Certain places like the gallery have broadcast "open comms" that are sent out to everyone on the gallery channel—notably the studio crew and camera team. I've watched magicians step into the gallery without a microphone on to complain about the camera crew and winced, knowing full well that every camera operator is listening to the rant.
I was also there when the talent removed their mic, left the studio, and got in a car to go to the train station, and we still heard them complaining. That's right. They'd left the building, removed their mic, and were down the road, and we could all hear them moaning about the crew. How? A runner was with them to make sure they caught their train, and the runner was sitting on their radio button.
Be nice.
This advice came full circle for me when I was young and given a new contract to sign. All my mentors advised me not to sign it. Not long afterwards, I was sat in the wings at the Old Vic theatre in London. Suddenly, the comms in my ear came to life as the microphone on the magician I was working for was turned on in their dressing room. I listened to the magician, my boss, and a colleague discuss their plans to replace me for about twenty seconds before removing the comms.
Not fun.
A good note is that you do not need to wear a microphone. Sound engineers will want you to wear one because it's easier for them to put one on you at the start of the day and forget about it. But if you think wearing a microphone will be troublesome for your stage illusion—perhaps it'll record the sounds of you contorting within a box—ask not to wear one. The host will hand you a handheld mic when you need it, or they'll stop and mic you after your performance.
If you're bringing an audience member on stage, they'll need to be mic'd, and for this reason, production often pre-selects them (there are other reasons too). My advice is to go with it but try to make sure they're not visibly wearing a mic before they get on stage so it doesn't look odd on TV.
Just because you're there, it doesn't mean you'll air.
As an assistant producer on a late-night talk show, I saw multiple magicians and talent acts get cut. What's crazy about late-night talk shows is the turnaround time and wild west nature of production. You shoot the show at six, and by ten, it's on the air.
