Don't let your exboyfriend meet up with you at your house.

He will pop back up sooner than you wanted and then tell you he still loves you and a weird scary way and then he'll know where you live.

Don't roll a penny on your steering wheel.

You won't be able to balance the penny vertically and then you will get it caught inside the steering wheel. It will act as a connector and set off your horn for minutes at a time while you drive. You will then have to pay $90 for your dealership to dismantle your steering wheel to find the penny.