how to use macros

ok i'm a programming noob and I've got no fucking idea about how to use macros. I'm trying to disable the full screen toolbar in microsoft word so I can read an ebook without the thing in my way. I know the code to put in, but I've got no idea what to do with it!

Sub FullScreenToolbarToggle()

Dim msg1, msg2, Title
msg1 = "Enable Full Screen toolbar."
msg2 = "Disable Full Screen toolbar."
Title = "Full Screen Toolbar Toggle"

    If CommandBars("Full Screen").Enabled = False Then
      If MsgBox(msg1, vbOKCancel, Title) = vbOK Then _
            CommandBars("Full Screen").Enabled = True
    ElseIf CommandBars("Full Screen").Enabled = True Then
      If MsgBox(msg2, vbOKCancel, Title) = vbOK Then _
            CommandBars("Full Screen").Enabled = False
    End If

End Sub

Help plz?