I run a media agency with clients across digital and traditional media, but my background is digital (25 years); we manage PPC (performance) and brand campaigns from the tens of thousands to many millions per year.

As u/Unbelievablemonk said (but got downvoted), we use a specialized headhunter to recruit highly skilled digital media folks (those with years of PPC and experience working on 7-figure budgets). A good headhunter knows which talent pools to talk to, does their own reference checks *beyond* just what the candidate’s references will be, and they guarantee their placement (in other words, if we hired them and they don’t work out, the headhunter is on the hook to source us a replacement candidate. Yes, it’s expensive and yes, hard to find a great headhunter but once you do, for the more senior roles it’s well worth it.

Referrals are another great source. People who work for us, who worked with someone they felt would be a good fit. Yes, we offer a bounty to our staff if we hire someone, but I suspect most would do it anyway because they’d be happy to work with people they trust & like.

Lastly, we post in our industry communities (Facebook groups for the ad folks in our city, and on LinkedIn). More filtering here for candidates, and lots of interviewing to get a sense of their skills. Hit or miss whether we always hire people that are an ideal fit for us — but that’s normal of anyone I’ve hired, in any department, over my career.

I have heard of some companies/agencies who make candidates do a “test”, but I prefer the old-fashioned interview style to get a sense of fit.