First cut a strand of hair from your head. Next, fill in a questionnaire about your state of health and send it, with your hair, to an address on the other side of the country.
Then sit back and, while not exactly by return of post, you will in due course receive relief from whatever ailment is troubling you. It could come in the form of a pill or a potion, but it's just as likely to come in the form of healing vibrations, transmitted from the person to whom you've sent your hair.
What is it? Magic? Witchcraft? A load of twaddle? No, it's radionics, the largely unexplained art of healing someone you've never met, who is hundreds, even thousands of miles away.
There are only 80 or so practitioners of radionics in Britain and Rebecka Blenntoft is one of them. She's also the secretary of the UK Radionic Association and, like her colleagues, she gets to the root of her patients' problems by holding a pendulum over their hair sample (or "witness", as it's called), and seeing what happens.
"We get the information by interrogating the witness," she claims. "I will ask question after question, some looking for a yes or no answer, some looking for an answer that will quantify the health or otherwise of the patient's various physiological systems [aural, visual, skeletal]."
So, as well as rotating in a clockwise direction for "yes", and anticlockwise for "no", the pendulum also gives scores out of 100 when placed over a sort of healthometer chart.
"It's quite a time-consuming process, because you have to go through every part of the body," says Blenntoft. "It's also quite tiring, because you have to stay very tuned in and focused on the person you are treating."
Once she's identified the problem area, she enters an eight-digit numerical code into a black-box-like radionics machine (they prefer the word "instrument"), either via a digital keyboard or a set of dials. Followed by the relevant treatment instruction (restore, rejuvenate, elasticise, for example). Almost simultaneously, it is claimed, the patient will experience some form of improvement in their condition.
You don't believe it? Neither did Blenntoft, until she saw the effect a radionic diagnosis had on a dog in her local village (the treatment can be used not just on humans, but on animals and even crops and soil).