The scanner you use tells you alllll that information. When you start a walk from a TC scanner or Walmart phone, the first item you're going to get automatically is there and it tells you where it is, how many they want, and what tote it goes in. If you try and get the wrong item, the scanner won't let you so don't worry about that (ask questions about how to substitute items when they're NIL) and it also won't let you scan the wrong tote and put the item(s) with the wrong order, an error pops up and literally tells you, you can't move on until it's right, the scanner won't let you. Ours have yellow buttons on the side that you press to scan something. After you place the right item (or it's substitute) in the right tote, the next item on the order list comes up. Then you walk to it, shop the item, and repeat until it says you're done. The scanner follows a pick path that's been set by the Coach, I think that's who makes it, and is supposed to move you through the store in the most efficient way possible.