Just won millions in the lottery? Congratulations! Here's what to do — and more importantly, not to do — to avoid making some very big mistakes.

Whether you bought a ticket yourself or got some as a stocking stuffer, could that $1.15 billion Mega Millions jackpot have your name on it? The odds may be against you − like 1 in 302.6 million − but that doesn't mean you can't prepare.