Garside began boxing as an amateur in Duncan, British Columbia, Canada after seeing Christy Martin fight Deirdre Gogarty on a Mike Tyson undercard in March 1996.

On 4 December 1999 in the 57 kg final of the 2000 Canadian National Championships at the Sportsplex in Campbell River, British Columbia, Garside defeated Michelle Collins of Alberta by an 11-1 score.

On 29 August 2002 in Kansas City, Missouri, Garside won a unanimous decision over USA Champion Jennifer Han of El Paso, Texas in the Women's 126 lb division.

[citation needed] On 18 November 2005 at the Shaw Conference Centre in Edmonton, Alberta, Canada, Garside won the WIBA super-bantamweight title with a 10-round unanimous decision over Lisa Brown.

[1] On 16 February 2006 at Harrah's in North Kansas City, Missouri, she won a third round TKO over Kim Colbert, in a scheduled six-round non-title bout[1][2] After vacating her super-bantamweight title, Garside claimed the vacant WIBF featherweight championship with a unanimous decision win over Laura Serrano on 4 November 2006 at the Shaw Conference Centre in Edmonton, Alberta, Canada.