I was asked to make a shawl similar to a wall hanging made by their grandmother 99 years ago.. this is my take on it..
Gauge is not essential, any size yarn can be used with a corresponding hook, however if using thread I would recommend doubling the thread in order to get a adult size.
The shawl requested was to be extra large, using a h hook it is about 6 ft long. I think a g hook would give you a more detailed appearance.
This is a chart with limited written instructions.