The Grease! actress' home is in a very "private" area so she doesn't need to worry about onlookers when she wants to sit outside naked in the sun.
Asked when she was last naked outdoors, she told Empire magazine: "Where we live is very private. We've had lots of rain lately so if the sun comes out I will strip off and jump out.'
"That would be in the last couple of weeks. Please don't tell anyone where I live!"
But when Olivia is in her garden, she's always keeping an eye out for snakes.
Discussing her biggest fear, she said: "Heights I think. That or snakes; I am definitely living in the wrong country for being scared of snakes.
"In Australia we've got tons of them, dropping down in front of you, hiding under your seat."
When she's not able to soak up the sun outside, the 70-year-old singer-and-actress finds clearing out her junk very "satisfying" and loves getting housework done.
Asked what she's good at, she said: "Tidying up. I've been watching that lovely Japanese lady [Marie Kondo].
"She's just gorgeous. She walked into a room that's a mess and goes, 'Yay!'
"I'm not going 'Yay' but I'm obsessed with tidying up.
"I haven't done the Marie Kondo folding yet, but I do the thing where you hold it and if it doesn't give you joy, it goes. It's very satisfying."
Olivia also confessed to having seen her own musical Grease! more than any other movie ever made.
She said: "I'd probably have to say 'Grease!' because I've sat through a number of premieres and re-runs. So that's the film I've seen the most."