make an application as a service

I want to make an application that can add as a service in NT. What should I add in my code? and What should I pay attention for?

[leolin@]

SERVICE_TABLE_ENTRY DispatchTable[] =
{ { TEXT("ServiceName"),
ServicesFunction},
{ NULL , NULL }
};
StartServiceCtrlDispatcher( DispatchTable)
is the most important funtion to create
service.

There is Wizard sample under system in this site.

please check it out
leolin