"Clients [need to] feel you know what you're doing," says billing consultant Joanne Mitchell. She advises mentioning previous employment or doing volunteer work in your area of expertise to begin establishing credibility. "I volunteered with a women's clinic, helping them organize their records," Mitchell says. "They gave me leeway to do it the way I felt it needed to be done."

Mitchell was able to use that experience later as a consultant. She also has taught community education classes on starting a medical billing business, which helped strengthen her presentation skills.