Don't get scammed. Here are two rules that you should ALWAYS take into account:

1. If it looks too good to be true, IT IS! Turn and walk away.
2. NEVER give someone your social security number, a credit card number or any other personal information unless you are absolutely sure of the situation. If someone asks you to pay them for an opportunity where you will (seemingly) eventually be paid back, it's a SCAM.

If you want to learn more about some of the known scams floating around, please read this: Avoiding Scams: The Basics.