Hide Excel Tabs-Heading-Formula Bar on Opening

[pivotguy]

I would like to have a full screen upon opening an excel file. Can you tell me where should I place the code
so that the workbook is displayed full screen with no Formula bar, heading and tabs etc.

Sub HideExcelItems()

Application.DisplayFullScreen = True
Application.DisplayFormulaBar = False
ActiveWindow.DisplayWorkbookTabs = False
ActiveWindow.DisplayHeadings = False
ActiveWindow.DisplayGridlines = False

End Sub