Here is the deal, wait till harvest time, allow the plant to continue to go past it's optimum harvest day, eventually it will start to sense it will not be pollinated, and it is gonna die, so it will produce male flowers in a last ditch effort to survive. Collect pollen from now hermie plant, and harvest your buds. Doing it that way reduces the risk of have a seedy plant because it went hermie and pollinated itself.