Talk to the instructors at Elstree about the route, run over it with them on your map.
If you want Sunday Lunch at Dunkerswell you will need to book it - its very popular.
Dunkerswell is busy at times, listen out well in advance, the radio is A/G so is not always quick to reply. Make sure you have found Dunkerswell, there are two other disused airfields nearby.
Watch out for Parachutes, and gliders from North Hill.
Have fun