The lateral pull down machine targets the back muscles, in particular the latissimus dorsi (lats).
First of all, adjust the pads so your legs fit comfortably and firmly underneath whilst also ensuring your feet are firmly on the floor then adjust the weight appropriately. You also have a choice of attachments such as a v-grip or wide grip.
To get into position grasp the handles of the grip whilst standing, then sit down ensuring your legs are under the pad and feet are secure on the ground. Slowly lower to a seated position. Once ready, lean back slightly, pull the bar down squeezing your shoulders and slowly return back upwards - avoiding locking your arms.