At the end of October 2010 I went to a live roleplay event that had a neolithic setting. You can't go there wearing your army boots of course and the group I was in decided we'd try to go as authentic as possible.
Where they bought Iron Age shoes (the setting is at the end of the Stone Age) I decided I wanted closed shoes and would make them myself. Based on Native American moccasins. (probably not really neolithic, but I'm going to a roleplay game not a reenactment event)
What a work!!
It took me 4 tries to find a pattern that would actually work. (see link below, I used the first drawing as a pattern)
I have made about 6 mock-ups (paper, fabric, thin leather) before cutting the real leather I was going to use.
In the images above you see 3 photos of the first try of sewing the thing. (They're labeled '1st try')
The used piece of leather in all the pictures is the same, the only difference is the manner of sewing.
In the first try the thread does not show on the outside. Though it looks tidy, it was not wearable because the stiff leather seam was poking me on the inside.
In the second try I overlapped the leather of the toe-part instead of using the right-on-right approach. This resulted in a flat seam that does not poke me. You do see the stitching on the outside though.
For the heel I put the thickness of the leather against each other and used a crossing stitch. This is both functional and decorative.
There's no left or right shoe. They're both the same. Wearing them will shape them to my feet.
I've also made inner shoes out of scraps of sheepskin, with the wool fluff against my skin. This fills up the extra space I have in the shoe (it is no exact fit) and keeps my feet warm.
I nearly completed the rest of my costume: cow skin leggings, split leather loincloth, suede dress, loose rabbit skin sleeves, rabbit skin hat, deer/reindeer poncho (not started yet). I might post those too some day.
Result after a weekend of wear in cold, wet conditions: it took a day of rain and swamp-like forest floor to drench the shoes. Once wet you can only dry them at a campfire with lots of patience and they'll get soaked again after three steps in the mud.
Still, for a first try and those conditions they held out quite long.