try this
Code:
Sub Toggle_Paper_size()
With ActiveDocument.Styles(wdStyleNormal).Font
If .NameFarEast = .NameAscii Then .NameAscii = ""
.NameFarEast = ""
End With
With ActiveDocument.PageSetup
.LineNumbering.Active = False
.Orientation = wdOrientPortrait
.TopMargin = CentimetersToPoints(0.63)
.BottomMargin = CentimetersToPoints(0.5)
.LeftMargin = CentimetersToPoints(0.95)
.RightMargin = CentimetersToPoints(0.63)
.Gutter = CentimetersToPoints(0)
.HeaderDistance = CentimetersToPoints(0)
.FooterDistance = CentimetersToPoints(0)
.FirstPageTray = wdPrinterDefaultBin
.OtherPagesTray = wdPrinterDefaultBin
.SectionStart = wdSectionNewPage
.OddAndEvenPagesHeaderFooter = False
.DifferentFirstPageHeaderFooter = False
.VerticalAlignment = wdAlignVerticalTop
.SuppressEndnotes = False
.MirrorMargins = False
.TwoPagesOnOne = False
.BookFoldPrinting = False
.BookFoldRevPrinting = False
.BookFoldPrintingSheets = 1
.GutterPos = wdGutterPosLeft
If .PaperSize = wdPaperA4 Then
.PageWidth = CentimetersToPoints(45.89)
.PageHeight = CentimetersToPoints(55.87)
Else
.PaperSize = wdPaperA4
End If
End With
End Sub