You can record session notes, outcomes and attendance about an event’s guests by using the Add Your Post Event Update button that appears in the Event Actions panel of the Event page
Steps
Click the Add your Post Event Update button
It will take you to a version of the Create Story page for this event.
Complete the form - there will be options to add in details for each guest
Press Save
Your event update will appear at the bottom of the Event page in the Event Timeline section
The button only appears if a survey has been added to the Event Category. See how to design the event attendance form.
Surveys used as the Event Attendance Form often include text fields that are completed for each guest. Turn on One Field per Contact in your Survey