Here is a brief description of how to use the major switchboard functions:
1) conference: you select one of your contacts (who is online, of course) then you click "conference", if your contact accepts you will see a new panel showing the status of your conference, and you will be able to hear each other. Now, as the conference initiator, you can add other contacts of yours (note: everyone wanting to conference has to have everyone else in their contact list). You add another member to the conference by selecting them from your contact list and hitting conference. On the conference panel everyone will see the new conference member appear, and will also be able to hear and speak to them. You can repeat this procedure for as long as your bandwidth holds out :).
2) call: similar to conference except you can only talk to one contact. As you can see this is actually a special case of the more general conference, but the option remains for user clarity.
3) vmail: select a contact press the "vmail" button, the vmail record dialog box should popup, and then use the controls on the vmail record dialog box to record and preview your message. When you are satisfied with your message you then click send and the message will be put in the vmail box of your contact (note: they do not have to be online to receive vmail), a email will also be sent to your contact notifying them that they have a new vmail from you.
4) text: this is classic IM. You select a contact press "text" and then a texting panel will come up. On the texting panel there are two boxes, one which will show your textual conversation and one which you can type into and then send text messages with.