Learn how to get started using green screen with iMovie for Mac. Click on a time-stamp below to jump to any part of the video. Add a Video Background to a Green Screen Clip 0:17 - Add a Background Clip to the Timeline 0:23 - Add a Green Screen Clip to the Timeline 0:38 - Add the Green Screen Effect 0:48 - Adjust the Length of Your Clips 1:18 - Duplicate the Background Clip 1:26 - Extend the Background Clip 2:08 - Trim the Green Screen Clip 2:47 Add an Image as a Background to a Green Screen Clip 3:19 - Add a Background Image to the Timeline 3:24 - Add a Green Screen Clip to the Timeline 3:33 - Add the Green Screen Effect 3:41 - Disable the Ken Burns Effect 3:53 - Adjust the Length of Your Background Image 4:35 Adjusting the Green Screen Effect 5:13 - Adjust the Softness of the Edges 5:47 - Isolate Areas of the Green Screen 6:03 - Clean Up Areas of the Green Screen 6:31