Just before his 40th birthday, Jeff Williams left the financial security of a full-time job to start the Go Smart Business Start-Up Center in Chicago. Over the years, Williams has coached and trained thousands of aspiring entrepreneurs and refugees from Corporate America like himself. A decade ago, he founded Bizstarters, which specializes in helping people age 50 and older start their own businesses. In this interview, he offers advice for would-be entrepreneurs who are currently working for someone else