Try not to use credit cards if possible, 90% of the people use credit cards on things they don't need and end up with almost double or triple the amount they owe. It's best to save and buy with your savings, no credit burden on your shoulders.
But if the problem is inevitable and you have to get a cred card, use the amount and try to pay back as soon as possible, because the longer the payment will take to get paid, the more you fall into the trap of interest.
If it is hard to pay back the sum on monthly basis, then consider a low cost loan as an alternative, you can do the calculation, a credit card debt of APR 16.8% of £2,500 over five years will cost £1,212 in interest. A loan at 7.8% will cost £527. A sweet savings of £685