Try to position yourself in a prominent location, particularly if the parking is difficult to find.
As people arrive at the start of the walk, check they have suitable clothing, drinks and food. If you think it is going to be very muddy, warn people so that they can put on gaiters and suitable boots. If there are a large number of people ask someone to be a back-marker - run through the route with them so that they have a rough idea where you will be going.
Before setting off, introduce yourself, welcome everyone (particularly newcomers), outline the walk route, the distance, the pace you expect to go, when you will be breaking for refreshments and when you expect to finish. Do a head count.
Under 18s should be accompanied by a responsible adult.
If there are any dog walkers, you should make them aware of the society's policy. Dogs are welcome at the leader's discretion but must be kept under strict control at all times. Extra care should be taken through farmyards, where animals graze and near private gardens and nature reserves. The dog owner should have sufficient water and a bowl for the dog as well as bags to pick up any mess.