Pick a subject at random. Something you have perhaps heard of, but know little about. It can be related to your job, but should not be anything you ever deal with. For example, if you work as as a bank deposit processor, you might pick the subject of "city zoning laws governing the installation of an ATM in a public right-of-way." It's important that you not be able to hold up your end of a conversation on this subject.

Now, pretend you answer the phone and a stranger speaking in a carefully modulated voice begins asking you detailed questions about the subject you chose, and will not let you off the phone or the hook, until you answer them.

Congratulations! Now you have my job!