> breakdown of the materials
Sometimes, patches can look pretty. There's also a way to fix crotch blowouts by sewing the hole shut, almost like weaving new fabric on top of the existing one. When done properly, you can't even notice from distance. Now that's a skill I'd love to master.
Did Knoch sew that jacket? Sewing your own stuff seems to be a very decent hobby, even though it sounds gay. That's a skill that takes years of practice, though.
>Any tips where to find ressources for a first sowing project?
I'd try to find the sewing pattern of Wehrmacht M44, can't think of anything more primitive than that. It was designed to be extremely simple in production, after all.