The groups section

There are two kinds of groups in Connect: public and private. Public groups can be discovered and joined by anyone. Private groups can be accessed only by the creator and users who are invited in. Public and private groups are both listed under the Groups header.

Public groups are denoted by the tag symbol, and private groups are denoted by the lock symbol. To create a new group, locate the '+' icon at the top left of your Connect account (next to your team name). Then select "Create Group." 

Set the type of group you want to create and choose a name. When you name the group, you can't include spaces or special characters. You must use lowercase. You can invite colleagues to join the group now, or at any time after you create the group.