Stupid things are largely things that cause you not to put money into your program, or to take money out of your program. If you fail to become a multimillionaire DRIP investor practicing the InvestingForStudents.org Program it is probably because you have been guilty of doing stupid things. Some, but by all means not all examples of stupidities to avoid are: divorce, credit card debt, gambling debt, car payments, living above your means, substance abuse, going to jail, being under diversified, being under insured, making horrible investments and the list goes on and on.

On a personal note, under AVOID DOING STUPID THINGS, divorce, living above my means, and being under insured, almost done me in.