Button With Message Pop Up

This is probably very simple, but how and where do I add codes to the button where a confirmation message pops up? Like, "Are you sure you want to save?" or "Are you sure you want to exit?"

For Example: Save and Close button

Private Sub cmdClose_Click()
On Error GoTo Err_cmdClose_Click

DoCmd.Close

Exit_cmdClose_Click:
Exit Sub

Err_cmdClose_Click:
MsgBox Err.Description
Resume Exit_cmdClose_Click

End Sub


Private Sub cmdSave_Click()
On Error GoTo Err_cmdSave_Click

DoCmd.DoMenuItem acFormBar, acRecordsMenu, acSaveRecord, , acMenuVer70

Exit_cmdSave_Click:
Exit Sub

Err_cmdSave_Click:
MsgBox Err.Description
Resume Exit_cmdSave_Click

End Sub

Thanks in advance!