I too am impressed anyone wants to start one! Mine collapsed several years ago because no one would take any of the leadership positions and none of the younger members would do any of the committee activities. The culture has changed. Potential volunteers want to come in, serve, and leave. The need to have an Auxiliary with social activities, dues, an organizational structure, fundraisers, and so on died some time ago.
My suggestion would be to survey your volunteers and anyone else who would like to weigh in as to how involved they agree to be. If you can't get a solid number of individuals who will take leadership positions, manage committees and so on, you are in trouble from the get-go.