How do I arrange the rosters?

Open any roster via Reservation > Roster and click the Views button > Manage rosters.

At 'To show' you can determine which resources/rooms are shown and which are not
At 'Settings' you can, for example, adjust the number of days you want to display
Under 'Shared with' you can indicate whether the roster may be shared with Everyone or only with certain usergroups.
To do this, you must first create usergroups and then assign users to such a group.