Show me the designs in a presentation; apply designs ONLY to selected slides

This demonstrates how you can apply masters/designs to selected slide or slides rather than PowerPoint's rather odd default behavior of applying a design to all slides in a presentation:

Sub SensiblyApplyMasters()
    With ActiveWindow.Selection.SlideRange
       ' assuming you have a design named "Bob" ...
       .Design = ActivePresentation.Designs("Bob")
    End With
End Sub

If you don't know the name of the designs but want to do it by number:

Sub NumericallyApplyMasters()
    With ActiveWindow.Selection.SlideRange
        ' choices: Nobody, Bob, Carol, TedAndAlice
       .Design = ActivePresentation.Designs(3)
    End With
End Sub

What are the names/numbers of the available designs? This'll list them.
Press Ctrl+G in the VBA editor to display the Immediate window, where this information will appear.

Sub ListMasterNames()
    Dim x As Long
    For x = 1 To ActivePresentation.Designs.Count
        Debug.Print ActivePresentation.Designs(x).Name
    Next
End Sub

See How do I use VBA code in PowerPoint? to learn how to use this example code.

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