Individual stickers (or pre-printed prices on the label - that was a corporate innovation) that would be “rung up” on a cash register that would “register” each price, print it out on a receipt (another innovation) and then total it at the bottom.

UPC codes required stores to buy scanners and have digital cash registers instead of mechanical ones. I had a grocery store that couldn’t afford the scanners at first but eventually made the investment because all of the new equipment - and our vendors’ shipping styles - required it.

This question makes me feel so old!

Yes each item had a ticket on it. You had a machine that you dialed the numbers on. It would print out that price onto a sticker and fire it onto to the item. I loved those machines!

You added the amounts up manually on a cash register.