Start at St Dunstan's Church (80, St Dunstan's Street, CT2 8LS), on the corner of London Road and St Dunstan's Street.
If you are coming by train to Canterbury West Station, turn right on to Station Road, and then right again at St Dunstan's Street. It's a 7-minute walk.
If you coming from Canterbury East Station, it's about a 20-minute walk. To avoid walking along the busy ring-road (Rheims Way), it's best to cut through town. Walk out of the station via the bridge into Dane John Gardens, and turn left along the city walls and towards Castle Row. Walk along Castle Row and continue along Rosemary Lane until you reach the junction with Stour Street. Turn right and walk until you get to the High Street. Turn left up the High Street and walk straight up, through Westgate Towers and up St Dunstan's Street.
If you are driving, nearby car parks are Pound Lane and Canterbury West Station. You also might find street parking along Westgate Court Avenue (about 5-minute walk to the start of the tour) or Orchard Street/Queen's Avenue (under 5-minute walk to start). Make sure you double-check the parking times/zones on the street.
There is also a bus stop outside St Dunstan's Church. Buses which stop here include the UniBus. For more options, see https://bustimes.org.uk/localities/st-dunstans.