You may be able to Volunteer at any date you are available.
Through work search engines eg, indeed.com or seek.com
Officers are trained through their theological college now located in Melbourne. Civilians go to their website
To become a driver at the Salvo Stores you would need a HR licence. They usually advertise on Seek.com.
In the stores most people start out as volunteers and eventually become employed by the company.
You go to the stores and ask to become a volunteer