How to change and format the background of your PowerPoint slides to custom designs

You can change the background of your PowerPoint slides using the "Format Background" feature located in the "Design" tab.
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Powerpoint background tips: How to customize the images, colors and borders

PowerPoint has a great set of special effects, graphics, animations, and template themes. There’s just one problem: Everybody else has the same effects, animations, and template themes that you have.