This example switches the active window to normal view and sets the magnification to 80 percent.
With ActiveDocument.ActiveWindow.View
.Type = wdNormalView
.Zoom.Percentage = 80
End With
This example increases the magnification of the active window by 10 percent.
Set myZoom = ActiveDocument.ActiveWindow.View.Zoom
myZoom.Percentage = myZoom.Percentage + 10