I know somebody in his 50s, here in the UK, who owns three houses etc etc and he had problems buying some furniture on credit a few years ago. His credit rating was non existent as he had always paid cash for everything.
Get her phone contract in her name. (Probably the easiest to start with). The only credit cards she is likely to get are the high interest cards for people with poor ratings. If she pays it off in full each month she wouldn't be paying interest. Try Metro Bank for a credit card. They are far more relaxed about giving an account to people with a non existent credit rating. She might have to open a current account first.