The M20 is Closed for the show use M2 / A2 !
From Dover, head for A2, and show is on your right after 4 miles
From M25 anticlockwise(J2), A2 - Towards Canterbury / Dover
From M25 clockwise (J2), A2, M2, A2 - Towards Canterbury / Dover
By Ferry :
10 mins from Dover head for A2 (Canterbury), then on A2 for about 3 miles
By Channel Tunnel:
30 mins from the depot .Head for Dover and then same as above.