He first showed his works at an exhibition in Lublin in 1938. After the outbreak of war, he found himself in Romania and travelled to England via France. He took an active part in the war effort. In 1943, he took up studies at Edinburgh University College of Art. At the turn of 1944-1945, he participated in the war campaign in France, Belgium and Denmark. From 1945 to 1948 he continued his studies at St. Martin's School of Art in London and at London University, and from 1947 to 1948 he attended classes with Henryk Gotlib at the Polish College of Art.

Liszkowski arrived in Canada in 1949 with a three-year obligation to work on a farm. After finishing his contract, he began teaching drawing and painting in schools. His first exhibition took place in 1952 at the Adelaide House villa in Oshawa: "In the beautiful villa, until recently the residence of millionaire philanthropist R.S. McLaughlin, there is an exhibition of paintings by the painter Stefan Liszkowski, a Pole from Whitby. The exhibition was opened by the former premier of the province of Ontario and consists of 60 of his best oil paintings, drawings and charcoal sketches. Local newspapers praise the artist and augur a future for him" ("Związkowiec").

From 1951 to 1955, the artist taught drawing at the YMCA and the Vancouver Art Night School. In 1960-1961 he studied art history and anthropology at the University of British Columbia. Faculty Club, established at the University of British Columbia, purchased his painting 'Riders' in 1962, the painting 'Crucifiction' adorns St. Mark's College in Vancouver. For his abstract entitled 'Resurrection', Liszkowski-Leskard (he changed his name in 1960) won first prize at Spectrum 68 at the Vancouver Art Gallery.

Leskard was co-founder of the Art Directors Club, co-founder and president of the Vancouver Artists' Association and a member of the Advertising Artists and Designers Association. In 1967, the artist showed 75 pastels at the Vancouver Art Gallery. From 1969 to 1980, Stephen Leskard became head of the art department at Capilano College. The Federation of British Artists invited the artist, in 1970, to present his work at the One-man Show in London.

In search of inspiration, the painter travelled to Spain, Italy, France, Turkey and Greece, which was reflected in the themes and colours of the works. During the summers, the artist gave painting lessons at the Okanagan Summer School of Fine Arts. The artist uses oil, watercolour, pastel, ink, pencil and charcoal drawings, various printmaking techniques, as well as sculpture. Landscape, city architecture, figural compositions, nudes and portraits alongside abstraction and geometric formalism - this is the broad spectrum of Liszkowski-Leskard's creative possibilities.