He briefly attended St. Patrick's Indian Mission School as one of a few white students in his class, an experience that left a lasting impression.
Hess studied art at the University of Oklahoma (OU) under Emilio Amero, a prominent figure in the Mexican muralist movement.
[5] In 1951, he joined the faculty of Drake University where he taught graphic design, lettering, printmaking, painting, and related subjects.
His commercial art was featured in Life, Time, Fortune, and Newsweek and he designed numerous brochures and programs for events at Drake University.
Hess also developed his own phonetic alphabet of 40 characters that he named Tempered Notation, designed to align written and spoken English.
His designs were influenced by the Mexican Modernism of Amero, as well as Jean Charlot, who included him in a select group of assistants to execute Inspiration of the Artist, a fresco for the Des Moines Art Center (1956).
[10] The Riverfront YMCA was a major project showcasing five of Hess’ murals, including two exterior brick walls that were the first of their kind and drew national attention (1957–60).
He often chose religious or biblical subjects, as well as scenes of childhood and everyday life, including Judith Holding a Censer and Garage Sale.
In his early career, Hess worked in watercolor, oil, caseins, and egg tempera, before turning almost exclusively to acrylic on gesso hardboard panels.
[18][19] Hess also experimented with panoramic and vanishing perspective, and occasionally painted on accordion-pleated panels to create two different scenes, visible from two different angles.
Although his technique evolved over the course of his career, Hess generally painted with careful precision, using rich colors and somewhat flattened, geometric forms.
Hess similarly designed replicas of early stringed instruments – predecessors of modern violins and guitars – including the pochette, mandora, cittern, viol, and baryton.
He remained active in his home studio well into retirement, amassing nearly 200 paintings and making musical instruments, until Parkinson's disease curtailed these pursuits.
In 1997, Hess donated more than 50 of his handcrafted instruments to the Mabee-Gerrer Museum in Oklahoma, where the collection is a teaching tool for musicians and historians.