Muesmann studied architecture at the Technical University of Karlsruhe and the Technical University of Munich from 1899 to 1904, passing in Munich in 1904. He began a traineeship, initially working in practice in Rosenheim from 1904 to 1905. In 1907, Muesmann passed the second state examination in Munich and was appointed government architect (assessor in the public building administration).
From 1907 to 1914 he worked as a city architect in Bremen. Then he moved to Stuttgart as head of the city planning office. From 1919 to 1921, he worked as a lecturer for urban planning and housing development at the Technical University of Stuttgart. In 1921, Muesmann moved to Düsseldorf for a short time as head of municipal building construction (city construction director).
On 1 April 1921 he was appointed full professor of structural engineering and design, urban planning and housing at the Technical University of Dresden. In 1926 he attended he International Urban Planning Congress in Vienna and gave a lecture on the Großhaus and Kleinhaus and their significance for the urban organism. In November 1933, he signed the declaration of allegiance to Adolf Hitler by the professors at the German universities and colleges. From 1936 he headed the university working group for spatial research at the TH Dresden. He retired at the beginning of 1945.