The dust will fill about half of the 4oz jar. That is normal and correct to how much should be in there because it is 4 oz weight not volume. They want there to be room at the top so it doesn’t fly out when opened
Apply wax in the area you want to add texture, sprinkle a small amount of dust over the area before the wax dries. Work the dust into the desired area with a wax brush. Clear wax will act as an eraser to remove excess dust.