Ayer was born in Champaign, Illinois, on January 18, 1968, and grew up in Bloomington, Minnesota, and Bethesda, Maryland, where he was kicked out of his house by his parents as a teenager. Ayer lived with his cousin in Los Angeles, California, where his experiences in South Central Los Angeles became the inspiration for many of his films.
Ayer's upbringing in Champaign, Illinois, Bloomington, Minnesota, and Bethesda, Maryland, led to his expulsion from home at a young age. This experience, coupled with his time living with his cousin in Los Angeles, California, where he was exposed to the realities of South Central Los Angeles, shaped his artistic vision.