Hewitt did not initially go to university, and began her career on a Marks & Spencer management training scheme.[4] She later joined Lex where she managed a Volvo dealership in Bristol; Lex sponsored her MBA from the University of Bath, which she completed part-time from 1992 to 1995.[4][2] She became chief executive officer of the RAC in 2006 (which was part of the Lex group) until 2008 when RAC was acquired by Aviva.[3][4][5]