When creating your event, you can always enter Preview mode by clicking the Preview button in the top right corner.
You will open a new tab and view your event through the eyes of an attendee. Use this mode to:
check if the tab structure makes sense
preview your customizations
join sessions to check if the group settings are correct
and much more
Video:
More articles:
How to test your event when live: https://learn.krowden.com/en/articles/4831695-how-to-test-your-event-when-live