Gilbert attended Sioux City High School where she took secretarial courses, as well as weekly piano lessons. When she graduated in 1923, she attended Morningside College for six months before leaving and going into the music business. Part of this decision was based on the fact that in the 1920s, her father became ill, so Gilbert was needed to help support her parents. At this time, she self-taught herself the alto saxophone, as she was told it was not suitable for young women, and joined the Musicians Union in Sioux City.