Diebitsch worked with graphic designer Walter Heck to draft the well-known all-black SS uniform.

Also with his business partner, industrialist Franz Nagy, Diebitsch began the production of art porcelain at the factory Porzellan Manufaktur Allach.

In Hanover he completed his apprenticeship as a decorating painter after the First World War, because of his enlistment in the Imperial German Navy in 1915.

Diebitsch enrolled in the Design School of the Academy of Plastic and Graphic Arts in Munich on 29 October 1919.

When the Nazis came to power in 1933, Diebitsch moved his family to Berlin and there joined the Reichsverband Bildender Künstler Deutschlands (National Association of German Visual Artists).

In 1938 he received one of the top prizes at a House of German Art exhibition in Munich for his painting titled, Mutter (Mother).

He served on the Personal Staff Reichsführer-SS and designed a tapestry that was created by Elsie Seifert.It was removed from Heinrich Himmler's residence in Berchtesgaden in 1945 by a member of the 506th Parachute Regiment of the American 101st Airborne Division.