The first thing was to design and cut the pieces out of fabric. I used three simple pieces. One narrow strip for the tongue on two for the sides that are show in the image above. The shape are only approximate and were modified during the process. The first thing that I did was to sew a new longer tongue on top of the original one.
The side pieces were sewn together along the shorter back side and then attacked to the old shoe. I managed to do that using combination of sewing (to add some detail) and gluing to the sole. New shoes are much more resistant to water that old because of used material and gluing.
The eyelets for the laces are inserted alongside the whole length of the length.
And this is the final form of the shoe. In this picture the cover over the front black toe is still missing and has to be glued on.