Draw the elbows together as much as possible and make passes with the strands from one elbow to the other so as to oblige your model to maintain this position (this is going to depend not only on the flexibility of your model but also on their capacity to bear the constriction that you will exert).

When you no longer have enough rope to complete a lap around the elbows, begin to wrap vertically around the horizontal passages connecting the elbows.