Hayman was born in London, and schooled at Malvern, before going to New Zealand for a decade where he began to paint at Dunedin. In 1947 he came back to England, finding a home in West Cornwall (1950) and moving around from Mevagissey to Carbis Bay ('Dunvegan') and St Ives before returning to London in 1953.  In 1964-65 he spent a further year in St Ives, joining the Penwith Society. 

His work was visibly influenced by that of Alfred WALLIS, and he participated actively in group and solo shows. Though he finally returned to London, Cornwall was always evident in his work and subject matter, and he continued to visit with regularity. His wife was Barbara, and good friends were many, including George Phil Whiting.

For five years (1958-63) he edited The Painter and Sculptor, a magazine he established, and in 1988 his Painted Poems were published by the Louise Hallett Gallery. In 1987 his painting Events by the Sea (1970) was selected for the Looking West Exhibition organised by NAG with the Royal College of Art, in collaboration with the National Trust.