Becoming an "authority" can help as well. Having a public, professional, persona can help with credibility. I started off doing training, which progressed to a

Becoming an "authority" can help as well. Having a public, professional, persona can help with credibility. I started off doing training, which progressed to a book, which progressed to more training, which progressed to a free weekly webinar where I answer questions. In my tiny niche, prospective clients "know my name". If I'm asked to supply credentials it's easy to do, and there's usually someone on their team who's heard of me. It helps skip over the "can he do the work" part of the negotiation. Customers are happier to do projects, and pay more, if they are confident the project will actually succeed. Typically its not their own money they are depending, but project failures hurt their upstream reputation.