Wow. Just did a google search for twisted fringe. Noc Bay has a detailed instruction sheet that involves twisting a long strip of leather & letting it relax upon itself creating a rope look. These are usually done to add individual laces onto fans. Twisted Fan Fringe

But it seems we are all looking toward fringe that is cut from the assembled material. Here there's some tricks... has a thread that discribes getting the leather wet & a method using a clothespin & electric screwdriver Twisted Fringe

Another site suggested wetting the leather with 50-50 alcohol/water <rubbing alcohol - not fire water> that 'opens' the leather and allows it to stretch. Alcohol Suggestion

"We do not inherit the Earth from our ancestors,
we borrow it from our children."