From the pattern:

Until recent times, women of the Faroe Islands wore a type of shawl like the Norwegian school model… To make it fit well, however, they knit a gusset down the center with decreases.

The classic Faroese shawl has a shape like two right triangles put together with a tall, skinny trapezoid in between.

The pattern has a schematic as well as two sorts of charts for optional openwork: one which shows both yarn overs and decreases, and one which just shows yarn overs. General instructions are also written.

Yarn, gauge, and needles are not specified.

Page 78.