Photoshop, basically- I tend to find a decent base map to work from and then essentially trace over the basic elements using vector shapes, adding things as I go. Long process but I think the end result is nice.
Very nice, though I would have thought that Austria would have brought Burgenland, those large German cities in Moravia, Istria, Friulian speaking areas, and land connecting the Sudent together with it when entering this union. Could you make a map showing it internally like with Prussia? It also seems that they didn't lose to France or Italy, so why did they give up land, non-German land even, without getting Luxembroug or something in exchange?
A plebiscite was organised in Alsace-Lorraine (France was neutral in the Great War), and Germany ceded Trentino (and the German colony in Somalia) in exchange for Italian neutrality (Italy was formally allied with Germany's enemies).