Hairston grew up in Southern California. In high school, he was an All-Orange County defender at Foothill High School. He attended the University of California, Davis and, in 1993, was named a starting linebacker for UC Davis Aggies football. In his junior season, he broke his neck during a Division II playoff game, damaging his C5 and C6 vertebrae. In 1995, he was signed as an unrestricted free agent to the San Francisco 49ers. After a year with the team, he transferred to the Denver Broncos before retiring in 1996.