Quilliam's watercolour mantra is select, simplify and suggest. He starts his works by selecting a subject, often from sketches made on location, adding or subtracting features to create a pleasing composition. Next, time is spent on simplifying the work to suit the watercolour or watercolour and pen medium. A reasonably detailed pencil drawing is made, finally he paints the scene, again trying to suggest rather than define the detail.
A love of travel has seen him practising his art throughout Europe as well as at home.