If you wish to select all components in the drawing area, use the keyboard shortcut Ctrl +A.

If you wish to select all components in the drawing area except for a few components, there are two ways:

1. The first option is to select all components as seen above (Ctrl + A), and then deselect the few components by holding Ctrl and clicking them.
   
   
2. Another way is to select the components that you do not wish to be selected and then invert the selection.

To do an inverted selection, follow the steps below:

1. Select the components that you wish not to be selected (Figure A).
   
   
2. Go to the Edit menu and select Inverse selection. The components that were selected earlier are now deselected while the rest of the components in the drawing area are selected (Figure B).
   
   The keyboard shortcut for Inverse selection is Ctrl + I.

Figure A

Figure B