You could use a macro like:
Code:
Sub ChangeOrientation()
Application.ScreenUpdating = False
Dim sMT As Single, sMB As Single, SML As Single, sMR As Single, sMG As Single
With Selection
.InsertBreak wdSectionBreakNextPage
With .PageSetup
sMT = .TopMargin
sMB = .BottomMargin
sMR = .RightMargin
SML = .LeftMargin
sMG = .Gutter
.Orientation = (.Orientation + 1) Mod 2
.TopMargin = sMT
.BottomMargin = sMB
.RightMargin = sMR
.LeftMargin = SML
.Gutter = sMG
End With
End With
End Sub
in the document's template and, perhaps, assign it to a shortcut key.
For PC macro installation & usage instructions, see:
http://www.gmayor.com/installing_macro.htm
For Mac macro installation & usage instructions, see:
https://wordmvp.com/Mac/InstallMacro.html