Read the instructions: "Tempo: unmeasured". "The whole song with expression and feeling ad lib, always, from beginning to end!".
This was composed in 1919. From https://en.wikipedia.org/wiki/Erwin_Schulhoff,
He was one of the first generation of classical composers to find
inspiration in the rhythms of jazz music. Schulhoff also embraced the
avant-garde influence of Dadaism in his performances and compositions
after World War I. When organizing concerts of avant-garde music in
1919, he included this manifesto:
Absolute art is revolution, it requires additional facets for
development, leads to overthrow (coups) in order to open new
paths...and is the most powerful in music.... The idea of revolution
in art has evolved for decades, under whatever sun the creators live,
in that for them art is the commonality of man. This is particularly
true in music, because this art form is the liveliest, and as a result
reflects the revolution most strongly and deeply–the complete escape
from imperialistic tonality and rhythm, the climb to an ecstatic
change for the better.
IMO, do whatever you want - which may or may not involve actually playing the instrument. The basic principle of Dadaism was to reject logical reasoning in favour of nonsense, irrationality, and intuition.