To change a property for multiple guests in a single operation:
1.Select multiple guests in the 
Guests, 
Groups, 
Floor plan, 
Table plan or 
Schematic panes using Ctrl+click/Shift+click (Ctrl+A to select all). Note that you can select tables or groups to edit the properties of all guests sat at those tables or belonging to those groups.
2.Select Edit>Guest Property and then choose the appropriate property and value. Choosing ... will display the Edit Guest Property window.
Note You can use menu keyboard accelerators to access this menu without using the mouse. For example, you can type Alt+E+Y+G+M to change the selected guests to Male. This is quicker than using the mouse to select Edit>Guest property>Gender>Male. Hold down the Alt key to see the menu keyboard accelerators.
Video with audio (1:48 minutes)
See also: