Abstract: A process for manufacturing an article of waterproof footwear such as a boot is provided. The bottom of the lower where the sole is attached is initially left open so that any seams can be sealed watertight and any additional features, such as insulation and liners, can be added in an easier and more precise manner. The present method also makes it easier to custom fit footwear and make footwear in half sizes by taking the guesswork out of determining the actual inner dimensions of the footwear because these dimensions can be directly observed.