The right inner packaging fixes and cushions the contents and thus protects it from damage during shipping. The heavier and more sensitive the contents, the greater the padding effect must be!
Cushion the goods to be shipped on all sides and fill all cavities to prevent the packaging from being pressed in. Suitable materials (filling material) for padding include, for example, several layers of bubble wrap, packaging chips or also crumpled paper (e.g., compressed kitchen paper/newspaper) in sufficient quantities.
Note the order: place heavy contents at the bottom, light at the top and delicate objects inside. Avoid direct contact of the shipping goods with the outer packaging (approx. 5cm distance, padded with filling material) and with each other, and also ensure there is no slipping of the material in the package. Cavities increase the risk of damage to your package.