Born in Nipawin, Saskatchewan, Byers spent a year with the Notre Dame Hounds before beginning his major junior career in 1981 with the Regina Pats of the Western Hockey League (WHL). The following year, the Boston Bruins selected him with a second-round pick (39th overall) at the 1982 NHL Entry Draft. His gritty style earned him a spot with Team Canada at the 1984 World Junior Championships in Nyköping, Sweden. Byers showed promise by scoring 32 goals in each of the next two seasons with Regina, but it was his 153 and 154 penalty minutes in each of those seasons that would be a better measure of his future professional career.