To display fly-over help for each navigator button at runtime, set the navigator ShowHint property to True. When ShowHint is True, the navigator displays fly-by Help hints whenever you pass the mouse cursor over the navigator buttons. ShowHint is False by default. 

The Hints property controls the fly-over help text for each button. By default Hints is an empty string list. When Hints is empty, each navigator button displays default help text. To provide customized fly-over help for the navigator buttons, use the String list editor to enter a separate line of hint text for each button in the Hints property. When present, the strings you provide override the default hints provided by the navigator control.