To start an Instant Mssage conversation, click on the Instant Message Link at the bottom of the personas profile. The Instant Message application will then load and you can send the user a message and add them to your contacts.
If a member is online, the ONLINE highlighted message is shown at his profile in search results or in any listing on a site. If they are not online they will receive it the next time they log on.
If you want to contact someone who isn't online you can still send them an Instant Message but they will not receive it until they next log on.
You can chat, see user status, IM with several users at a time.
You can switch your instant message setting to away by moving the AWAY SWITCH from green to red. You can also mute the volume by clicking the speaker icon.