comedy series creator Philip Differ comes up with a football analogy when talking about his alternative life as a stand-up comedian, and the choice of material to use.
"It can be tough," he says, his grin highlighting his understatement. "You've got to decide on the material that will suit a particular crowd you're about to appear before.
If they're older, you can do nostalgia stuff. If they're younger, you need to factor that in with the references. And if they're neddish, say in a bar, you need to be tough.
"But it's like taking a penalty; once you decide where you're going with it you don't change your mind because if you change direction they will smell fear and you will die up there on stage and it will be horrible."
Philip has had more than 20 years of experience as a comedy writer, writing for the likes of Rikki Fulton and Jonathan Watson.
But 10 years ago, despite the prospect of imminent death on stage, he found himself haunted by the idea of becoming a stand-up.
"I'd been thinking about it for ages but somehow it all seemed unethical," he says recalling the time. "I was afraid of jumping the fence. I felt I should leave it to the performers.
"Then one day, I met Fred MacAulay, and said 'I want to ask you something, Fred. A wee bit of advice.' Now, he thought I'd be talking about accountancy. (Fred's previous life).
"Anyway, I told him I fancied having a go at stand-up and he said; 'What are you doing next Tuesday? I'm on at the Stand (Comedy Club) so why don't you do five minutes, and we'll find out if you actually enjoy it."
Philip, who lives in the South Side, was bowled over. But he agreed. He was all set to make his name outside of writing. He was all set to show comics he'd worked with over the years, he could write and deliver material. But the build-up to the gig was torture.
"In the week before I was full of angst and couldn't sleep at night. During the day I'd sit in Newlands Park and watch the birds, thinking I wish I was that free of responsibility."
However he worked hard on his material, and it got him a result.
"On the night, Fred was really encouraging. It wasn't a great night for me, but I got a few laughs, just enough to make me want to continue.
"And I learned more about doing comedy as time progressed. I learned to build in a pause, to let the audience laugh. And when they did it was exhilarating."
He also learned you can't ever predict how an audience will react.
"Sometimes you walk on and say hello and you get a laugh. They take to you or they don't. At other times, you get nothing. But the most important thing is to sound confident. You're the pilot on a plane and they need to believe you'll take them where they want to go."
He adds: "Audiences don't like extremes. You can't be too young, too good looking, too smart."
After 10 'decent gigs', Philip began to feel he had arrived. He never reckoned on becoming the next Billy Connolly but it could become a second career.
"Then one night at the Stand, I bombed. I don't know why. It was so bad I could feel the sweat running down my belly. And I started to say to the audience, 'What's wrong with you?' It was the longest five minutes of my life and it made me realise how it could all go wrong."
Philip's material has varied over the years, from ad-libbing to observational.
"Last year I was going through an improv phase but at times I got lost up my own close, not knowing where I was going, so I decided I go for a more structured set and the theme this year is My Cosmetic Surgery Hell.
"The idea came about from my experience a while back when some blood vessels burst on my nose. No-one seemed to notice but me, but in my head I felt I had this Alex Ferguson nose and I had them treated. Then it became worse.
"But it all made me think about vanity, and the show is really about getting old."
l My Cosmetic Surgery Hell, Oran Mor, The Glasgow Comedy Festival, March 22, at 8pm.