Last year, someone said to my wife: "It must be a laugh a minute living with a comedian." It is. She's constantly in hysterics. Rather too much, to be honest. The problem is that, unlike most careers, our job defines us: it's not just what we do, it's what we are. As a comic, you're expected to be able to produce zingy one-liners at the drop of a hat, like a superhero whose superpower is an endless supply of killer knock-knock jokes. "Tell us a joke then," people often say when they find out I'm a comedian. I always reply: "The concept of comfortable tights." I don't think it's what they want to hear. But you can't expect a comic to be funny all the time. Eventually, everyone needs to wind down.
So it's essential, especially during the fringe, to have some down-time. Comics who are always "on" are dangerous. A simple trip to the toilet can become a 15-minute set complete with warm-up, interval and encore. So what do comics do with themselves when they're not on stage? Well, Josie Long swims in the sea, and Hannah Gadsby plays pitch and putt.
I like to do something different. For me, winding down means doing things other people take for granted. I like to hang around restaurants at midday, pretending I'm on a lunchbreak, too. I sit near people who work in offices and laugh at all their stories, about their awful bosses, about all the overtime they have to do. If anyone asks, I'm called Mary and I'm a secretary. In fact, we're workmates. Since it's holiday season, I can say I'm a temp and that's why they don't recognise me. And they let me in, especially if I say: "Who do you have to sleep with around here to get some stationery?" There are always problems with stationery.
Their normality is my relaxation: a world of order, rules, regulations and structure. Of appraisals rather than stars, of PowerPoint presentations rather than posters, of clients rather than audiences. No one asks me to tell them a joke, but I always slip one in anyway. Old habits die hard.
• Susan Calman is at the Underbelly on Bristo Square until 27 August (www.edfringe.com)
• This article was amended on 16 August 2012 to correct the spelling of stationery.
