From VoIP.ms Wiki
The Conference feature allows several people to dial into your DID number to be bridged together in the same conversation.
Conference provides the host with a dashboard monitor that allows organizers to monitor and control different aspects of the conference call in real time. Press the “Start Recording” button to get a recording of your conference call that you can listen and download after for any purposes.
Start using the Conference feature by clicking the “Add Conference” button to create a conference entry. Once your conference entry is ready you can route your DID number to it from the Manage DIDs > Edit interface to start receiving calls into your conference.