Final answer:
If you are helping another customer when your customer walks in, you should acknowledge their presence and let them know that you will be with them shortly.
Step-by-step explanation:
If you are helping another customer when your customer walks in, you should acknowledge their presence and let them know that you will be with them shortly. This shows them that you are aware of their presence and that you will attend to their needs as soon as you are done helping the current customer. It is important to provide exceptional customer service and make them feel valued.
For example, you can say something like, 'Thank you for waiting, I'll be with you shortly. I just need to finish up with this customer.' This reassures them that you are aware of their presence and that they will be attended to soon.