To add an object to a set:
- In the Sets window, select a set in the Sets list. 
 
- Select the objects you want to add from the Viewer window. 
 
- Click Update to save the new objects to the set. 
 
To remove an object from a set:
- Select the object to be disassociated from its set in the Sets folder of the Scene browser. 
 
- Right-click the object and select Detach x From y Set in the context menu, where x is the name of the object and y is the name of the set to which it belongs. 
 
To remove multiple objects from a set:
- Select a set in the Sets list. 
The objects in the set are selected in the Viewer window. 
  
- Deselect (Ctrl-click) the objects you want to remove in the Viewer window. 
 
- Click Update in the Sets window to save the changes to your set.