To create a direct message group, follow these steps
1
Click the New message button above the members list in the team member panel on the right.
Create direct message group
2
In the panel that appear, select the users you want to include in the group by clicking the Add button next to their names.
Add users to group conversation
3
Click the Start conversation button at the bottom of panel. Your group is now created, and you can start sending direct messages to it.
Start group conversation
Note: If you select users who are already part of an existing group, a new group will not be created. Instead, the existing conversation will open, and you can continue by sending new messages within that conversation.