Hi JCOLLINS!
Here are a few different ways--
Below the logo on any board page, where it lists the number of your awaiting IMs ("Hey, JCOLLINS..."), click on the last part of that sentence. Click "New Message", add the username and message text (and a subject if you wish), then click "send message".
In the Info Center at the bottom of the home page, click where it says "Your Internet Messages" and then "New Messages" when the page comes up, etc.
Click on any member's name to open their profile. At the bottom of their profile (where you can also see if they're currently online), click "Send this member a private message", and all you have to add is the message text since the space for their username will already be filled in.
Enjoy!
(In the event that MB is also responding at this exact moment, which wouldn't be all that unusual, please feel free to compare our answers.
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