Born in Swansea, Wales, Lewis was educated at Dynevor School, Swansea and then at Balliol College, Oxford, receiving a BA, later promoted to MA, in Philosophy and Politics.
With fellow Conservative John Bercow - later elected Speaker of the House of Commons - he ran an Advanced Speaking and Campaigning course for more than ten years, which trained more than 600 Conservatives (including several current MPs) in campaigning and communication techniques.