How would your boss describe you?
Think of a time when a compliment from your boss made you feel great. What was the situation? Were you punctual, never called in sick and were dependable? Think of the traits that make an ideal employee in the eyes of a boss. Bonus if your boss will write a letter of recommendation for you! You can also refer to former employee reviews if you have some written reports to bring to your interview.
"My boss would describe me as being dependable, knowledgeable and a hard worker. I like to train those around me, and challenge typical thinking patterns to include outside-of-the-box solutions."
