Donít go crazy with your new plastic. If you transfer a big debt on to a zero per cent deal it is easy to get carried away and start adding a few extras next time you hit the shops. But new spending wonít come under the no interest category. Check what the interest rate is on any new spending you do carry out Ė it might be higher than it had been on your old card. Debt experts say that you should also try to eat away at your debt while your interest payments are on hold.