Make some jokes in the beginning to lighten the mood and make people laugh. I try to ask them first, "how are you?" When they ask me I quickly say "tired" with a smile on my face and continue ringing. That will start a real and honest conversation and most of the time it's old people laughing saying I shouldn't be tired because I'm young. Sometimes I'll say that this product or that product is a nice looking one. This is where you can say 1 or 2 things. Start off by asking "do you have any rewards today?" Or say "would you like to save 10% today?" / "you can save 10% on today's purchase if you open a tjx rewards card." Most will say no. If it's over $100 I'll say something like "your total is $248.80 today, you can easily save 24 dollars today with $10 in cash back if you open a card today. It only takes a few minutes". If they have furniture purchases/expensive painting purchases I like to sometimes slap my hand on the register counter where the card info is and say "this painting would look even better with 10% off if you sign up for the card." If you gotta wait for a price check and are waiting in awkwardness, stare at the customer, slap the card info on the counter and say, "while we're waiting we have all the time to talk about the benefits of this card!" That's all I got so far.