Here are some example lists you can create:
In HubSpot Marketing, navigate to Contacts > Lists. Here you can create a new list and choose to begin segmenting your contacts.
Event registrants - Registration property | Event Name | is equal to | [enter your event name]
Event attendees - Attendance property | Event Name | is equal to | [enter your event name]
Contacts who have registered for an event in the past month - Contact property | Last Registered Event Date | is less than | 4 weeks ago