Page Comparison

Launch Quicktime Pro. Click File/Open File...                              

Navigate to the file you want to edit                        

  

Set your IN and OUT points

Use the keyboard shortcuts i = IN   /   o = OUT                   Image Removed Image Added

Move the playhead to where you want the clip
to start. Press "i" on your keyboard.  Then move
the playhead to where you want the clip to end.                  
Press "o" on your keyboard.

 Frame by Frame accurate editing

you You can move the playhead frame by frame to get a very accurate 
edit by using the arrows on your keyboard.  Fine tune where you want
the IN and OUT points by using the arrows to get the exact edit pointUse the arrows keys to 
"fine tune" your edit.

Now that you have set the IN and OUT points for your clip you now
need to simply copy the section, open a new Quicktime player, and paste
the new clip section into the new player. 

Click Edit/Copy - this will copy the new section to the clipboard

Open a new Quicktime Player

Click File/New player - this will open a new untitled Quicktime player