Born in Bellefontaine, Ohio, Flora attended the Art Academy of Cincinnati from 1935 to 1939. In 1938, he met writer Robert Lowry, then a student at the University of Cincinnati, and the two launched The Little Man Press, a letterpress series of limited edition publications, for which Flora supplied illustrations, design, and layout. They collaborated on Little Man Press until 1942. (Lowry, a volatile and self-destructive literary turbine, later self-published many works under a revived Little Man imprint without Flora's involvement.)