1. Go to extensions, click on the gear cog on the upper right hand corner (underneath options and above search), and click add.
2. Change the type to “Simultaneous Ringing” and then choose the extension number, and click next (owner only matters if this ring group will be taking voicemails).
3. Click “next” and then “finish”.
4. This will open up the simultaneous ring group, click on the gear cog all the way on the right (middle of the page) and click “add extensions” to begin to add users to this ring group.
5. Change the final destination type to match where you want the call to go if it is not answered (extension, personal number, voicemail, or none).
6. Adjust the ring timeout override to change how long it rings on everyone’s phone.