E$-$Shop Logistics, an e$-$commerce fulfillment center, is struggling with inefficiencies in their order picking process, leading to delays and increased costs. They aim to optimise their order picking system to enhance productivity and reduce operational expenses. As a Facility Planner, you are tasked with redesigning the order picking process using the principles of order picking.

$($a$)$ Apply the principles of order picking to redesign the order picking system for E$-$Shop Logistics.