Finish the wizard shown above.
Note: The first time you call up code completion under Schliemann, per session, it is very slow.
The most interesting thing to do with this plugin is, assuming you're a developer on the NetBeans Platform who needs to let the user generate code, to look in the layer.xml file. Look at the Templates section, especially the definition of the two wizards. You'll see how a wizard is able to generate from a FreeMarker template, by referencing the template in the URL attribute, in combination with setting the FreeMarker scripting engine element.
The syntax coloring is based on code I found in the NetBeans sources. Until we officially support FreeMarker in the editor, this is the plugin that I will be using. Have fun with it. FreeMarker is really an incredibly cool way to generate code, as my blog entry yesterday went some way to show.