What is useful once you have shelter? One thought was to make mats - for covering the floor (particularly on muddy days), and for sleeping on. Mats to walk on need to be tough, and you don't want the cord that holds the pieces together to abrade against the floor. I've heard of cord sewn through the middle of bullrushes. Then the cord is protected, and the rushes make a nice spongy mat.
Another idea was to weave mats out of hay. A large loom could be made something like this. But the ends would be made from two straight pieces of dry wood, each about 2" diameter and 4' long. The top piece would be suspended about 6' off the ground, perhaps from a tree branch. The warp thread would be wrapped around it and the bottom piece, so that the bottom piece was about a foot off the ground. You get the idea - a loom suspended from a tree.
Then handfuls of hay would be pulled off the bale, and twisted into a relatively solid rope 1"-2" thick. This rope would be woven into the warp - splicing in more hay from the bale as needed. The result, hopefully, would be a nice soft sleeping pad about 5' long and 3' wide.
But ... what kind of cord do you use for the warp thread? It is sure to abrade against the ground, and then the whole thing falls apart. I haven't quite figured this out.
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