How do credit card companies try to trick you

Look at your statements carefully each month. Credit card companies are famous for changing your billing cycle. If you have been on a 30 day billing cycle, it is not uncommon for them to switch you to a 20 day cycle. This is how I got a late once.

You also need to be aware that when you transfer a balance to one of those snazzy 0% offers, the rate only applies to the balance that was transferred. Any new purchases might be at a different interest rate.

Keep in mind that your credit card company is not your friend. They are predatory and want to keep you in debt.