Despite the fact Australian Shepherd dogs have been bred as herding dogs, this doesn't automatically mean your pup knows what to do. What it does mean, is that most Aussies have a natural instinct to herd, but even then, your pup must still be trained to ensure he knows what is expected of him and how to follow your commands and cues.
Herding involves more than simply moving the herd around, it also involves allowing your pup to think on his own in certain circumstances such as when one animal wanders off. With Aussies, the training can be very easy, or it can be quite challenging. It just depends on your dog's personality. It also depends heavily on your training skills and the amount of time and effort you put into the training.
Using dogs to herd every imaginable type of domesticated animal from chickens to ostriches has been going on farther back than records exist. A properly trained herd dog will know how to do his job and follow verbal, whistle, and hand-signal commands. He should be able to move the herd from one place to another on your property or even in competition if you feel the two of you are up to it.
However, before you can start training your Aussie to herd, he must first know the basic commands. These are 'come', 'sit', 'stay', and 'down'. This is very important as not only will your pup be learning new commands to follow as part of his new skill, he will also be using several of the basics at the same time. Note, there is a significant risk of serious injury to your dog and livestock, your dog needs to be at least 1 year old before you start this training.
Because herding is a high-energy activity, you should take your pup to see his vet to make sure he is ready to take on this challenge. You will also need to choose your new herding commands, including "walk up" for bringing the herd to you from behind them, "away" for being on the left side of the herd to drive them to the right, and "come bye" for going on the right side to drive the herd to the left.
You also need:
The rest is all about time and patience on your part and cooperation on the part of your dog and the herd he is working with.