The former Queens High School pupil left Dunedin in 1967 and ended up working as a radio journalist in London.
Ms Johnson then worked as an assistant editor for Woman's Way magazine in Dublin, interviewing the likes of the late Spike Milligan.
As a hobby, she decided to enrol in an astrology course and the rest is history, or in the case of a budding astrologer then - the future.
"I started doing charts for people because I was so fascinated by it," she said.
"The charts are set up through scientific means; the interpretation is an art."
Ms Johnson started compiling horoscopes by hand using dates of birth and the position of the planets.
"Now we tend to do it all by computer."
Ms Johnson, who has combined horoscopes with psychic insights for thousands of people since 1980, said her clients had included folk singer Donovan and Australian actress Toni Collette.
Since 1991, she has also worked as a past life regression therapist, assisting people to discover previous lives - even discovering from a fellow therapist that she was once someone famous.
"I have been told I was Anne of Cleaves [the fourth wife of Henry VIII] in a previous life."
Her profession has drawn mixed reactions from people, and when she travels she lists her job as a journalist to avoid any inquisitive questions on arrival.
She enjoys returning to her home town, visiting family and friends every couple of years, and is contemplating a return home for good.
"It feels right," she said.
Asked to put her skills to the test by predicting the future of the Awatea St stadium, Ms Johnson consulted her tarot cards and delivered her verdict.
"The breakthrough will come in November. It is going to get Dunedin out of its lethargy."
