It is your choice.
You can basically do whatever you like in your session. There are no limits. You can host workshops, panels, keynotes, arrange exclusive meetings with the founders, organize a recruiting barbecue or pull-off a big party. Be creative!
A rule of thumb: A session should be around 60-90 minutes long and should take place in the host’s office.
And most important: the crazier, the more people will show up 🙂