Buy the plans for some ship you want to build. You can find in Internet many companies who are offering plans for model ships. Usually the plans include nice drawings for all the bulkheads you need to build the model. Normally only half of each bulkhead are shown. Make a template of stiff cardboard of each halfbulkhead.
Then buy a piece of suitable plywood (4-6 mm thick, preferably made of balsa or other softer wood which is easier to saw and sand), draw the whole bulkheads on the plywood using those half bulkhead templates. In this way you get both sides similar. Then cut them away using whatever saw you have (bandsaw, scroll saw, jeweler's saw, etc). Do the same with the keel. Glue the keel & bulkheads together attached to a sturdy baseplate made of some thick fibreboard or plywood. When everything is nice, straight and sturdy, you have to fair the "skeleton". That means sanding all the edges of the bulkheads at angles so that the planks will bend nicely on them. After this is done you can start planking.
Planks you can also buy from a hobby shop, have them done by a nearby carpenter, or make yourself if you have some sort of nice and accurate circular saw.
