There will be a much more readable schedule on the web soon. You'll get a con book when you register and they'll be printed schedules.
All kinds of things are going on at once. The games and viewing rooms are always going, and there are the panels to watch. You don't have to stay through all of anything, you can move from event to event as you like.
People will be hanging out hours before anything starts to get registered. Since usually about half of the people pre-register and half pay at the door, you want to get there in plenty of time to get your badge if you want to get to an event that starts at a certain time.