A master slide is a layout that can be used throughout a Presentation. You can create multiple master slides, and switch between them at any point in a Presentation. If you change any elements in a master slide, all slides based on that master are updated.
Creating a Master Layout
Click the Master Layout section in the Presentation Outline. Click Add Master.
Give your new Master Layout a name. You can now edit the master, adding text, graphics, colors, and formatting.
You may wish to create multiple layouts, to be used in a Presentation for introductions, informational slides and conclusions, or simply to vary the look of the content at key points.
Using a Master Layout
Right-click the name of your slide group and select Add Slide. A new slide will appear in your group with the default Master Layout. You can also right-click any slide in your group and select Add Slide to create more slides with the same layout.
If you wish to change the Master Layout for a slide, click on the slide. Click the Crown icon to select a new Master Layout for your slide.
Please note that you can’t edit the content of the Master Layout from an individual slide (with the exception of changing the background via the right-click menu). If you need to change other elements, you’ll have to return to the Master Layout itself.