private void createActions() {
		nextAction = new NextHighlightedRangeAction(tool, getName(), navOptions);
		tool.addAction(nextAction);

		previousAction = new PreviousHighlightedRangeAction(tool, getName(), navOptions);
		tool.addAction(previousAction);
	}
Create the actions and add them to the tool.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/navigation/NextPrevHighlightRangePlugin.java