Frequently Asked Question
Note: You need to be in a call for this feature to work.
Press the conference button on your phone when it is time to bring in the third party. The button you will be looking for is this:

Once you have pressed the conference button it will bring up the conference dialing screen. From there, dial the third party number and press send. As soon as you have the third party on the line you can then press the Conf/Call button to initiate the 3-way conference.
Your third party will now be joined on the same call. When the conversation with the third party is complete, you can then hit the Cancel button to drop the third party and resume your 2-way call.