Entrepreneurship is the great American dream. Nearly 57 percent of all Americans—and almost two-thirds of those under 30—would rather own their own business than work for someone else. Yet Dun & Bradstreet reports that 28 percent of all new businesses fail within the first three years, and 63 percent fail within six years. The American dream of owning a business can also turn into the American nightmare! Here's what you can do to succeed.