Complex sentence: From 1935 on he worked exclusively as manager of the advertising department and was editor in chief of the company newspaper "Dornier-Post" which appeared from the autumn of 1935 until July 1938.
Split into simpler sentences: From 1935 on, worked exclusively as manager of the advertising department. Was editor in chief of the company newspaper "Dornier-Post" which appeared from the autumn of 1935 until July 1938.