Over the years I’ve been given periodic opportunities to create designs for actual products, often times involving the entire packaging of a product.
Before sending things like this off to print, I’ve found it best to model and render 3D mockups of what the final version of a product would look like. Things like this help to sell the realism of how a product would be seen, and can often give you some insight on key details that you’d easily miss by focusing solely on a flat layout.