Artie T. opens his store in Waltham

Different models of self-checkouts have different personalities, and some work much better than others. Some machines have a mean and angry voice and tend to fight with the customers more than necessary. Other systems (e.g.: the model used in most Shop & Stop stores) can be a pleasure to use!

It saves a lot of time if you know the four-digit code of produce items you buy; it's much faster to punch in the number directly, rather than searching through all the pictures. If you don't remember it by heart, try to make sure the number is easily visible on whatever you're buying. For produce sold by weight, make sure to place it properly on the scale; for items sold by quantity, be ready to enter the count when prompted.

It's important to place items on the belt immediately after scanning. The machine does a verification by weighing and/or measuring items as they travel down the belt. This can be affected when an item falls down, so try to place top-heavy items steadily. Sometimes it'll reject a package of meat that you've placed into a produce bag, but if the bag is wrapped tightly to the package it'll usually work. Occasionally, a barcode will become wrinkled, especially on packages of meat. If the scanner can't read it, you can make it work by manually entering the number printed beneath the barcode.

When an item is rejected after scanning; an alert will sound, the item will be subtracted from your order, and the belt will start running backwards. Immediately remove the item from the belt and try scanning it again. If it still fails; press the "Help" button, but put the item aside and continue. An attendant will eventually come over and fix the problem; meanwhile, you can finish scanning the rest of your order.

If you're paying with plastic, swipe your card as soon as you start to finalize the transaction; if you press the buttons as displayed on both terminals as quickly as they appear, you can jump ahead of the game a bit. You only need to make a quick squiggle on the Jean pad; it doesn't verify your real signature.

Now comes an important feature of self-checkouts that most shoppers overlook: the Order Separator. Note in the picture below, the flat strip of plastic at the back edge of the bagging area. There are metal grooves that it fits into, across the end of the last belt.

If there's another customer waiting behind you, politely deploy the Order Separator as soon as possible; that way, the next person can commence scanning their order while you're still bagging yours. Their items will accumulate on the second belt, and won't get mixed up with your order. When you're done, swing the Order Separator back to its storage position again before leaving, so the next person's accumulated groceries can start flowing through to the bagging area.
     
^{Self-checkout with Order Separator in non-deployed position.}

With a little practice, you'll get up to speed and will be able to scan items very rapidly. Since you know what you're buying, it's possible to self-checkout your own order faster and more accurately than taking it to a professional cashier. Then, when you do patronize Market Basket and the cashier is bewildered by your bunch of greens, you'll be able to quickly tell her, " It's kale, 4627 ".