How do the "Secret Annexe" folk hide their existence

The Jews Hermann and Auguste van Pels with their son Peter, Fritz Pfeffer and the Frank family were the folk hiding in the Secret Annexe. They stayed inside, never leaving. They kept completely silent and keep the curtains drawn. They have a ritual in the morning, the afternoon and evening contingent to the working schedules of the warehousemen to keep the laborers from discovering them.