How to make the Pharaoh's Serpent (Mercury (II) Thiocyanate)

Warning: This experiments requires the handling of dangerous and volatile chemicals. It must only be carried out in a fumehood or outdoors. All chemicals must be disposed of properly. Everything will be contaminated with mercury/mercury salts. NOTHING CAN GO DOWN THE DRAIN OR IN THE GARBAGE. Only carry out this experiment if you can dispose of the chemicals and combustion products properly. Every step of this synthesis deals with dangerous or toxic materials. Gloves, safety glasses and a lab coat are mand