1. Open Teams and click Invite member.
2. Enter the person's email, or leave it empty to create a single-use invitation link.
3. Choose what they can do (permissions) and which channels they can use. If you select no channels, they can't publish anywhere.
4. Click Create invite. The person receives an email, or you send them the link.

They open it, sign in with their Wiply account and click Accept invitation. You can see pending invitations, resend or cancel them, and remove a member at any time.