Go to the top of your Direct Messages panel on the top right of the platform:
To send a message to one other person:
👉 Click on "New message" and type the name of the participant you want to start a conversation with.
👉 When you are done, click "Next".
To send a message to more than one person:
👉 Click on "New message" and type the name of the first participant you want to add.
👉 Once selected, you can type the name of a second participant, etc...
👉 You will then be able to add a name into the "Group name" field.
👉 When you are done, click "Next"
Change the settings of group messages:
👉 Open the conversation
👉 Click on the top right "..." icon
👉 You will then be able to change the settings.
Note - in messages with only one other participant, the only setting you can alter is the notifications.