This example sets the formatting for the bullet in shape two on slide one in the active presentation. The size of the bullet is 125 percent of the size of the first text character in the paragraph.
With ActivePresentation.Slides(1).Shapes(2)
With .TextFrame.TextRange.ParagraphFormat.Bullet
.Visible = True
.RelativeSize = 1.25
.Character = 169
With .Font
.Name = "Symbol"
.Color.RGB = RGB(255, 0, 0)
End With
End With
End With