1. Create a private message to the channel.
Open the channel and select Conversation from the top ribbon. You will be taken to a private message within the channel.2. Select the channel members.
In the To: field, type the name or @mention the people you want to add to the channel.3. Send the invite.
Once your list is complete, select send and the invite will be sent to the users.4. Confirm the addition.
After they accept the invitation, their profile will appear in the list of members within the channel.