Regan is a self-taught artist, having began exhibiting by spraying stencils in Melbourne’s laneway’s in 2002, under the name of HA-HA.

He is now known as one of the founders of the stencil art movement internationally, and his work is seen in galleries around the world.
He exhibited in 'Space Invaders', 2007, at the NGA, and in 'Contemporary Australian Optimism', 2008, at GOMA.
Stencil art workshops are another proponent of his practice and have resulted in 'Australia Week' - Port Moresby, (Australian High Commission), '50 Bridges Project' - Singapore, (Australian High Commission), 'Garma Festival' NT, 'Desert Harmony Festival' NT (Barkly Regional Arts), collaborations with Townsville Regional Arts QLD, to name a few.

Other achievements include international artist residencies such as 'La Martine' France, 'Saigon Outcast' Vietnam, and 'Australian International School' Singapore. Closer to home he has taught at Melbourne Grammar School and Footscray City High School, amongst others. He has also been a finalist in a number of national prizes.