I have (well, actually my wife uses it where she works!) the following code which may help you:-
Call SheetComparison("Sheet1", "Sheet2")
Sub SheetComparison(Sheet1 As String, Sheet2 As String)
Dim cell As Range
Dim diff As Integer
For Each cell In ActiveWorkbook.Worksheets(Sheet2).UsedRange
If Not cell.Value = ActiveWorkbook.Worksheets(Sheet1).Cells(cell.Row, cell.Column).Value Then
cell.Interior.ColorIndex = 8
diff = diff + 1
MsgBox diff & " differences found", vbInformation, "Check Differences"
Wherever in the code you see Sheet1 or Sheet2, change it to suit your spread sheet tab names. The color index number you can change to suit yourself.
I hope this helps.