Step 1: Be sure that each order has completed processing and matches (or at least is close to matching) it's weight before it entered the hub.
Steph 2: When you select "Complete Processing" you will then be able to release the order to a driver. Feel free to close the specific order - you will be able to release it later when the driver arrives.
Step 3: When driver arrives to pick up the various bags/orders to delivery back to their origin stores, open the active orders drawer from the home-screen. Once open, click on the blue button on the top right of your tablet that reads "Release."
Step 4: After selecting the release button, you will arrive on a white screen with a list of order that are ready to be released by a driver. In order to easily release each order, press and swipe your finger to the left on a specific order. After you've swiped that order, you will simply click the blue "Release" button that appears.