Shimmin was born in Douglas in 1960 and educated at St Ninian's High School and the Worcester College of Higher Education.
He was then a teacher (Physical Education, Mathematics, General Studies) from 1982 in several areas of the UK - Crewe, Tamworth, Knowsley before returning to teach in Douglas (St Ninian's High School) where he was also Head of Year from 1989-96 [REF] until entering politics.