So it is your first time sailing a dinghy, here are the key tips to get you going:
Stepping into a boat:
Dinghies are designed to roll from side to side so when you first step in to the boat go in to the middle. This will ensure the boat doesn't tip to one side.
The helm (the person steering the boat) should always sit on the side opposite to the sail i.e. with the wind blowing over their back. If it is light winds the crew should sit on the opposite side to balance the boat. As the wind gets stronger the crew moves into the middle of the boat. In heavy winds the crew will sit on the same side as the helm to keep the boat flat.
A dinghy can be steered by the rudder, the sails and balance. Initially we just focus on steering with the rudder. To steer the boat you push or pull the tiller. The tiller is a stick that connects to the rudder. If you push the tiller away from your body the boat will steer to the left i.e. the opposite way to which you pushed. Similarly, if you pull the tiller towards you then the boat will steer to the right. You only need to make small smooth movements with the tiller to steer the boat.
The first time you sail we will set you off on a course called a Beam Reach. This is the simplest point of sail and a good place to start sailing. In a beam reach you want to steer so as the wind is at 90 degrees to the boat i.e. when seated as the helm the wind is blowing directly into your back.
Sail setting / speeding up and slowing down:
The ideal position for the main sail (the biggest sail) on a beam reach is for the sail to be out over the side of the boat at 45 degrees. To adjust the sail position pull or release the main sheet (the rope that is attached to the sail via some pulleys and the boom). If you let the sail out further than 45 degrees the boat will slow down and evetually stop. To speed up pull the sail main sheet so the sail comes back in towards the boat. If the wind is causing the boat to lean away from the helm let the main sail out to bring the boat back to being flat or to speed up keep the main sail where it is and instruct the crew to move over to the side of the helm.