Firstly, you should consider talking to your bank. Ask them if are eligible to apply for a loan or credit card. The credit limit on that card may not be very high but it will provide you an opportunity to get a better credit score and apply for a better limit credit card in the future.
If you are not eligible for a credit card at your bank, consider getting a small loan. Smooth cash flow in the existing accounts can help build credibility, even though your credit score is not very high.
Sometimes, it is easier to obtain a department store credit card. The APR percentage on these cards is likely to be very high but again these credit cards can give you the chance to improve your credit history. Getting a department store credit card is relatively easy. Never miss a direct debit payment as this can have a very adverse affect on your credit rating.
Applying for low balance credit cards is also a good idea. If possible find a person with good credit rating who wants to co-sign for the card. You can also put down a deposit to get a secured card. If you fail to make a payment, deposit will be cashed.