It's hard to put my grandfather's directions into words but basically he said to wear it so that when you sit down, the weight helps with modesty, if you get my drift. My practice is to wear it low and raise it until I find that place, which has a comforting pressure on a place that enjoys comfort. This also argues against cosmetic sporrans: if there's no weight, it's going to bounce around while walking and not help modesty when you sit down.