Guillaume was born in Quebec City in 1978. He began studying music at the age of twelve. After a foray into guitar and flute, he discovered his true passion for the saxophone and focused seriously on that instrument under jazz musician David Parker. He then studied classical music under Bruno Turgeon at the Cégep de Sainte-Foy while continuing to study jazz with Jean-Claude Gagnon. Profoundly drawn to and inspired by jazz music, he completed a bachelor's degree in jazz interpretation in 2005 and a master's degree in 2008 at Université Laval, where he studied under the renowned jazz musician Janis Steprans. He was a finalist in the Jazz en Rafale contest in 2006 and a semi-finalist the following year. Guillaume plays all of the four main types of saxophones as well as the flute and the clarinet. In addition to teaching music, he plays with a number of different groups in a mix of musical styles: jazz, lounge, classical, Latin, swing, and pop. He also freelances with such renowned bands as the Big Band Roland Martel, the Latin band Saudade under Jacques Bourget, Moondance Orchestra and others. Always keen to hone his skills, Guillaume stays on top of his musical game by being involved in a number of musical projects at all times.