Onyejiaka was drawn to the world of fashion and pageantry from an early age, despite the limited for Nigerian women to participate in these fields at the time. In 1963 she competed in Miss World Nigeria, a pageant organised to select the country's first ever representative at Miss World (The Miss Nigeria Organisation were yet to acquire the international pageant's franchise), and emerged first runner-up behind 16-year-old Martha Bassey. However, despite her victory, Bassey was disqualified on age grounds, leaving an opportunity for Onyejiaka.[4]
Onyejiaka faced harsh criticism from Miss World Nigeria organisers who deemed her unsuitable to represent the country, branding her as 'ugly'. Although Miss World organisers Mecca Dancing had accepted Onyejiaka as Bassey's replacement, Miss World Nigeria refused to send her abroad. After Mecca Dancing declined to pay for her flight to avoid favouritism accusations, Onyejiaka independently funded her Miss World participation in London, becoming the first Nigerian woman to compete at the pageant.[3]