Depending on the position, becoming a stage crew member might require a combination of experience or training plus some background in music, theater, or art. Additionally, knowledge of lighting, audio (live sound), or working in film or TV would be helpful. Working as a volunteer at school or community productions and events could be a way to get started and gain experience. Some colleges offer majors in stage production and design. Apprenticeships and internships are sometimes available.
Once hired, you may need to join a labor union. Reaching out to the union local in your city could also be a way to get information on how to become a stagehand. The stagehands’ union is the International Alliance of Theatrical Stage Employees, or IATSE.