General:

Always pack in reverse order of density. Place heavier items toward the bottom of the box and lighter items toward the top or a separate box all together.

Always put the greatest amount of cushioning material on the top and bottom of each box. The cardboard walls are not a sufficient barrier.

Pack heavier items in smaller boxes. A larger box of regular strength is not designed to take an excessive amount of weight. Using a larger box makes it more difficult to both lift and stack. A heavy duty box can greatly eliminate the "crunching" effect that may occure when the boxes are lifted or stacked.