Finding clients for a test engineering company

If you were me, and trying to start up a software test engineering consultancy that helps companies get their software quality back on track (everything from helping build test strategies through to concrete automation frameworks and CI/CD pipelines), how would you go about finding clients?

I'm struggling to find anything beyond augmenting teams as a senior contractor but I'd like to take it a step further and find multi-person contracts as an agency instead. It's relatively easy to find these projects for product development but quality is far harder (it seems). Has anyone had a go at this before?