Using VZO Mobile Video Phone
First of all make sure you have somebody in your contacts list or know his/her VZOchat ID exactly in order to make a call. You can find many intresting friends in VZOchat members directory!
Then you can follow the screencast below to find out how to make a video call using VZO Mobile Video Phone application on your communicator or smartphone.
From VZOchat client
VZOchat Support website has in details explanation about VZOchat usage and about how to make a video call.