Nice, simple gestures.
It's true, when I'm at the checkout line and just smile and say hi to whomever, you can see the physical change and body language of the cashier.
Simple gestures go along way.
I recall one of former co-workers mentioning to our entire team about 60 colleagues how polite and professional I always was on the telephone with everyone.
Good morning, afternoon, evening.
CRT leader-my name
How can I help you?
Even answering personal calls, it amazes me how people haven't been taught how to answer a phone or how to ask for the person they are looking for.