To make money on such 0% credit cards – there is a catch, by which the uninformed end up paying 20%+ for using the card.
Once you have the loan amount on the card – make sure you pay off the minimum amount each month (best to set up a direct debit, so you never forget) – once in default, you will loose the 0% and be charged the standard rate for the card.
Second, throw the card in the back of a drawer and never use it for any purchases. Otherwise the terms of the card are such that you will pay off the 0% loan first, while accruing charges on your spending at 20%+, which will only get paid off once you clear the 0% loan.