So here is the basic shape I made. I cut the edges before I could peel it off the original.
You can spot that the zero layer's not smooth. It's the one I made only with help of water. I'll have to add some paper to this outer side.
The border needs special care. I took a piece of cord and inserted it inside. It will be a buttres for further construction.
I attached it with several amyled strips.
Covered with paper. In this state it's almost ready for painting which I'm particularly looking forward to;-)