The first picture shows a pencil sketch - a pencil sketch produced by me, and using a set of downloaded plans of SMS Hamburg produced by unknown member, rescaled to 1/300th scale.
The second is of a piece of 'hard foam' or 'foam balsa' that was given to me at an exhibition, where models were being produced from computer-aided drawings and programs. The material I have is in fact scrap material left over and usually thrown away. It is very easy to work and can in fact, be marked with a fingernail.
The next set of photos show the initial stages of construction, cutting strips roughly 22mm wide, squaring off the sides and cutting to length, then marking and cutting the sides to produce a chamfered profile. The photos show the construction much better than my description.
The bow and stern profiles were then cut and sanded using a piece of sandpaper stuck to a sheet of hardened glass with double-sided tape. Because the material I use is so easy to sand, the main problem was making sure I hadn't sanded too much. Detail sanding was then done with a nail-or-manicuring sanding stick.