For example, I have an Amex Platinum card, which offers some brilliant benefits – free worldwide travel insurance, free access to airport lounges, a great rewards scheme and it even comes up with random one-off offers. Last year, for example, it had a one-week-only 20% off everything in Selfridges. What a week that was. It also has amazing service – real people at the end of phonelines and everything. But for all this, I pay £300 a year and I've never quite worked out whether I'm ahead of the game yet.

There are websites where you can check whether the rewards you are getting are worth it – www.rewardchecker.com is pretty comprehensive. You will need to decide whether you want a card that gives cash back or shopping/airmiles/reward points. If you shop a lot in one shop – say, John Lewis – it can make sense to have its card as it should offer you plenty of juicy freebies and vouchers to encourage you to do more shopping there. Ditto for a BA/Virgin credit card if you do a lot of travelling, though check the interest rates on this type of card as they can be hefty. If your spending habits are pretty disparate, then a cash back card may be the best idea.

The key thing to remember is that if you're getting charged exorbitant amounts of interest or a huge amount of interest, you're probably better off not having the rewards. If you don't pay off your credit card in full every month, then forget rewards and just go for the one with the lowest rate of interest. If you do, then put as much as you can on the card – shopping, holidays etc. These cards all reward big spenders.

So now, I think I might take my own advice and see if my fancy card is really worth it.