While working in customer service, I have come to like many types of people. However, there are always those nightmare customers who are never happy, never satisfied, and always complain. What fun would it be to discuss the nice ones when there's so much more to say about the minority of customers—the bad ones?

1. Just smile.

You're actually not allowed to do anything else.

2. The customer is always right.

Seriously. The customer is always right, even when they really, really aren't.

3. Every day is a good day.

Even if it's the worst day of your life, as far as the customer is concerned, every day is the best day of your life.

4. I have mastered the art of talking while smiling.

I don't know how great it looks, but I can do it.

5. I can roll my eyes while simultaneously sounding pleasant over the phone.

(I am also able to mouth to my coworker how annoying the customer is being.)

6. I can smile and look truly grateful when they say I can keep the change, even though it's only $0.66.

I have also mastered that smile when someone asks says, "I'll need change," and it ends up being $1.28.

7. "I'm so sorry."

My apologies actually sound sincere. "Ma'am, I want to offer my sincere apologies for the [two minute] delay on your order."

8. Especially while serving, someone is inevitably going to do better than you.

Many serving jobs involve earning one's own tips. Some days someone else will do better than you. That's just how it is.

9. Customers sometimes continue to talk to each other even while you're standing there.

10. You need the job.

Quitting is out of the question. Suck it up, sweetie.