Here are a few thoughts for you to consider:
Treat the customer in front of you as the reason you have your job.
Treat customers like people and not problems.
Connect person to person.
Show that you care.
Listen without interrupting.
Realize if they have a problem or if they are upset, it's not personal.
Help them sincerely and respectfully. And, if you can't do it on your own, or if you don't know the answer, get someone to help you.
Most of all, treat your customers as you would want to be treated if you were in their shoes. Treat them as you would a guest in your own home.
Good luck and have fun.