You can create topics within the various conferences available in the forum. In order to post a message within a forum, you have to create a topic first.
Follow these steps to create a new topic:
Click the Groups tab on the left navigation bar.
Click the Group Memberships icon. The Active Memberships page appears.
Select the group in which you would like to create a new topic. The Group homepage appears.
To scroll down, click the arrow button. Click the Forum button. The Forum page appears.
On the Forum page in the Interaction column, select the new topic link.
The Create Topic page appears.
Type the Subject and Description and click the Create Topic button.