When she was 41, Mrs May was diagnosed with bowel cancer, leaving her with a colostomy bag she would have for the next 49 years.
Her husband Bill died of leukaemia eight years ago.
She has been an active member of several cancer society groups since her diagnosis.
"It only holds you back if you let it," she said.
Each day she gets up to bake muffins to take to neighbours, friends and those who have dealt with cancer.
"I turn on the oven the minute my feet touch the floor."
At 6am each day, the energetic retired sheep farmer jumps out of bed and doesn't stop. She believes the trick to a long and healthy life is keeping busy.
Mrs May started an osotomy group in Invercargill while farming near Winton, and since she moved to Frankton in 1980 has been part of the cancer society group there.
The group gets together every two months to bake and visit those who have been affected by the disease. She finds nothing more satisfying than helping others in need.
She whipped up some cheese rolls for the Wakatipu Community Church fair at Lake Hayes at the weekend- the trick to a good one is "good tasty cheese, onion and a pinch of salt and pepper".
Nibbling on the freshly-baked batch of muffins and bumble-bee truffles made fresh that morning, I couldn't help wonder if the youthful looking grandmother and great grandmother felt her age?
"I don't even think about it. I don't have time," she replied.
That's not surprising when she tells of four separate visitors before 3pm that day and her active swimming group of 12 seniors who meet twice a week.
She plans to keep her 90th birthday bash fairly quiet because she has "done enough partying".
After extending a birthday invitation to a reporter she met 30 minutes earlier, she kindly offered some advice worth sharing.
"Growing old is like a bank account; you withdraw from it only what you put into it."
