Just contribute definitions for new words - descriptions of locations/language/events/characters taken from the books
We've got a
suggestion form that you can submit to and either myself or Simguinus can approve it to make it public, or if you want to be more prolific then I could make you an Assistant Historitor or something.
All I normally do is read a novel, jot down some main points about the character or location and then re-write it as a coherent definition. As long as it's researched information and not direct copying from a GW source (e.g. copying the GW description of Tzeentch if you added a definition for the Chaos gods) then it's an encyclopedic definition.
The other idea I had recently was an extension of the Encyclopedia into articles. I've not put a definition in for Glossia yet, but when I do it might be interesting to extend things like that into an article about creating Glossia code and leave the definition as a definition with a couple of examples.
Unfortunately, as per usual, I need more helpers and I don't know enough people who I trust who have the free time to spare