The daughter of Puerto Rican parents, she was born in New York City and grew up in the Spanish Harlem neighborhood there.
After completing high school, she worked in a store and volunteered with the Legión de Maria.
She returned to New York City, where she worked for a financial institution and as a program coordinator for United Bronx Parents.
Between 1970 and 1978, Cardona worked for ASPIRA of New York, an educational service group, first as a counsellor and later as director for a counselling program.
She returned to school and received a bachelor's degree from Goddard College in Plainfield, Vermont through an independent study program.