"I did whatever was necessary. I took Devo's [Walden's] Range Rover to the panel beater, I went to the Ponsonby butcher to get meat for an agency barbecue, I cleaned the boardroom and I made coffee. I did that for about six to eight months," recalls Wilson.
"That part-time job was free, so it's nice to walk into TBWA today for paid employment."
In taking on the role, Wilson will work alongside TBWA Group chief executive Catherine Harris and chief creative officer Shane Bradnick.
Harris said that Wilson's arrival comes amid a period of growth for the agency.
"Paul is an exceptional leader, a brilliant partner to clients and has proven time and again that he creates world-class, disruptive and effective work.
"He also embodies our values and is a hell of a lot of fun to be around."
Wilson has known Harris for 20 years, with the pair first meeting when they both worked at Singleton Ogilvy & Mather in the late 1990s.
There has been no shortage of executive roles floating around the industry recently, with a number high-profile departures at major agencies.
Asked why he chose to join TBWA, Wilson says it came down to the leadership at the agency.
"Shane and Catherine really complement each other so well," he says.
"They've got very different personalities, but a really strong vision and ambition for the agency. They've got a really clear view on what they want the agency to achieve."
TBWA works with a number of sizeable clients, including ANZ, 2degrees, Asahi, the Warehouse and Fonterra.
The agency has also enjoyed a period of leadership stability at a time when other agencies are currently undergoing significant changes – it's a point the agency even made in a cheeky full-page advertisement in the Herald.
Wilson says his responsibility will be to ensure that TBWA consistently delivers high-quality work for its clients, while simultaneously building a strong culture within the agency.
This is always a tricky balancing act, but Wilson remains of the view that advertising businesses can be built sustainably for both clients and agency staff.
"If you just chase creativity and awards, it'll be at the expense of your people or your clients," he says.
"Alternatively, if you just chase new business growth it can be the expense of your people and the quality of the work.
"Growth's important, creativity and building strong brand platforms and ideas are important, but so is the health and the wellbeing of talent. You need to make sure that they want to be there every day."
Wilson argues that industry leaders can't just focus on one area at the expense of the others.
"As a leader, you need to constantly be monitoring each part of the business," he says.
One of the major challenges facing staff in the advertising industry is that job security can be challenging, given the growing prominence of project work and the tendency of clients to pitch their business every few years. This can be detrimental to the wellbeing of staff, who are sometimes uncertain about what the future might hold.
So how do you ensure security for staff and industry that's insecure by its very nature?
Wilson notes that the onus rests on leadership to be smart with the way it spends its money, particularly in years when things are going well.
"You need to be cautious with your financial management," he says.
"Your investments in talent or anything else need to be considered. Agencies need to understand that you might have a skyrocket year, but something different the next year. The leadership has a responsibility to provide a secure base.
"It's about building close relationships with clients so that you can get more information and an understanding of upcoming work, so you can have a clearer picture of what's coming."
Rather than focusing on the inevitable peaks and troughs of any business, Wilson argues that it's better to look for sustained growth over time and focus on bringing the strategy of the business to fruition.
With a strong creative team and an impressive collection of clients on his new portfolio, the challenge will now be for Wilson to bring that vision to life as he picks up the reins at TBWA this week.