Final answer:
For an improvised tourniquet, use a flat, soft material that is at least 1 inch wide to avoid further damage to the skin and tissues.
Step-by-step explanation:
When creating an improvised tourniquet, the preferred band would be a flat, soft material that is at least 1 inch wide, such as a scarf, necktie, or a piece of cloth. This is because narrow materials can cut into the skin and underlying tissue, causing further damage. The tourniquet band should be wrapped tightly around the limb, between the injury and the heart, and secured in place to effectively stop the bleeding until professional medical help is available.