First check your printer properties, it may have a duplex feature.
If not, the following VBA code is worth a try.
--
Jim Cone
San Francisco, USA
http://www.realezsites.com/bus/primitivesoftware

Sub PrintBothSides()
Dim pg As Long
Dim TotalPages As Long
Dim AdjustedCount As Boolean

ActiveSheet.DisplayPageBreaks = False
If Len(ActiveSheet.PageSetup.PrintArea) Then
Beep
If MsgBox("Print area has been set, do you want to continue? ", _
vbInformation + vbOKCancel, " Printing Both Sides") = vbCancel Then Exit Sub
End If

ActiveSheet.DisplayPageBreaks = False
TotalPages = ExecuteExcel4Macro("Get.Document(50)")

'Print Odd pages
If TotalPages Mod 2 = 0 Then
If TotalPages 1 Then
TotalPages = TotalPages - 1
AdjustedCount = True
End If
End If
For pg = TotalPages To 1 Step -2
ActiveSheet.PrintOut From:=pg, To:=pg
Next 'pg

Beep
If MsgBox("After printer stops, turn pages over and reinsert in printer. ", _
vbInformation + vbOKCancel, " Printing Both Sides") = vbCancel Then Exit Sub

'Print Even Pages
If AdjustedCount Then TotalPages = TotalPages + 1
For pg = 2 To TotalPages Step 2
ActiveSheet.PrintOut From:=pg, To:=pg
Next 'pg
End Sub
'-------------

"CINDY"
wrote in message
I AM TRYING TO PRINT EVERY OTHER PAGE OF A 180 PAGE DOCUMENT SO I CAN THEN
TURN IT OVER AND PRINT THE OTHER SIDE? ANYONE KNOW HOW