Every new schedule item starts with one people list, called Speakers. If a session has people in different roles — presenters, facilitators, moderators — you can give each role its own list. Attendees see each list as its own labelled group on the session.
To add a list:
In the schedule item, click Add list below the last list.
Choose People.
Type a name for the list, like "Presenters". As you type, Yapp suggests names you've already used on other sessions in this schedule, so the same role is spelled the same way everywhere.
Click Add. The new list appears below the others, ready for you to add people.
The same button adds a list of documents — choose Documents instead of People.
If another list on the same schedule item already uses the name you typed, Yapp asks you to pick a different one.
A new list stays hidden from attendees until you put someone in it — a list with nobody in it doesn't show up in the app.
Related articles that might be helpful:
Start with the guide to lists on schedule items
See how you can add people to a list
See how you can rename a list