With Three-Way Calling you can set up your own 3-party conference calls.
To use the Three-Way Calling feature:
Once you are on the line with your first call, press and release the
switch hook or flash button to hear a second dial tone.
Dial the number for your second party.
When the second party answers, press and release
the switch hook or flash button.
Your three-way call will begin.
When finished with the call, simply hang up.