How do I add more than one service to an appointment?

video1.0<iframe src="https://www.loom.com/embed/b696d83a4df640e0afff679d77dccabb" frameborder="0" width="1920" height="1440" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>14401920Loomhttps://www.loom.com14401920https://cdn.loom.com/sessions/thumbnails/b696d83a4df640e0afff679d77dccabb-9bcd68389dd6ddfd.gif52.694How do I add more than one service to an appointment?