Then, she set up a website and emailed friends about it. Or, what she describes as "unabashed, shameless advertising for people I knew".
One weekend, CIO New Zealand saw McCallum working on her craft at a party for a community organisation.
"What I really enjoy is it is creating and transforming something for the kids or the clients," she says, as she takes on continuous requests from the children for different shapes — flowers, dogs, robots, cartoon characters
She finds a "loose parallel" between her full-time role at Beca during the weekday, and as a balloon sculptor.
"Kids can be quite specific on what they want," she says. "They want this colour and they want this loop around there. I try to make it for them, and tell them what I am doing so they feel involved, and they have a sense of ownership."
It is the same with IT, she says, as she holds up one of her creations, a bright orange balloon shaped like the cartoon character Nemo. "Our clients know what they want. I just think it is important to involve them along the way so they own it and they have skin on the game."
"I find the adults are just as excited about the balloons as the kids," she says. But the adults seem to "challenge her a little bit more" with their requests for more complicated designs. "They like Eiffel Towers."
There was one time, however, when her balloons failed to elicit a smile. This was when she was making balloons for the residents of a rest home. "It was quite a hot day and a couple of balloons were popping."
One of the residents, "must have got a bit of a fright", she says. "When the balloons popped, he said: 'It is just like being in the war'... So I left him alone."
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