Oyama began performing stand-up comedy at 17 years old. In 2012, she was a state finalist in the Class Clowns competition. That year she also performed at The Sydney Fringe as part of "Barely Legal - Australia's Best Young Comedians" alongside Neel Kolhatkar and Aaron Chen, and performed on Dan Ilic's FBi Radio show. Oyama became a writer for the children's sketch comedy show You're Skitting Me, and made her television debut performing stand-up comedy on SBS 2 in 2014.