The idea of using treats to train is often equated with bribery. Truthfully, dogs do what works. If using treats gets them to do what you want, then why not? You can also use the world around you as a reinforcement. Every interaction you have with your dog is a learning opportunity, so when you think about it, you probably don’t use food very often except during active training sessions. So why does your dog continue to hang out? Because you reinforce him with praise, touch, games and walks. Just remember, the behavior should produce the treat; the treat should not produce the behavior.
Prong collars (also called 'pinch collars') are a series of chain links with blunted open ends turned towards the dog's neck. The design of the prong collar is such that it has a limited circumference unlike slip collars which do not have a limit on how far they can constrict on a dog's neck. The limited traction of the martingale chain combined with the angle of the prongs prevents the prongs moving close enough to pinch. The collar is designed to prevent the dog from pulling by applying pressure at each point against the dog's neck.
You can start training your dog before they're of age to compete. Begin by working on basic obedience and teach your puppy to sit, lie down, come, heel, and stay. Your puppy will also benefit from attending training classes where they will learn basic obedience and get used to working around lots of other dogs and people. Having your pet take and pass the AKC Good Citizen Test is a helpful step.
There is an ever-growing list of agility sanctioning organizations. The ones you’ll hear about most often in the US are NADAC, AKC, and the USDAA (see below for a more complete list of national and international groups). Each organization has its own rules and style. For example, NADAC courses are spread out and focus on speed. They often challenge the handler to send their dog through the course at a distance. USDAA courses are “tighter” and more technically challenging.
Martingale collars (also called limited-slip collars) are usually made of flat nylon with a smaller fixed-length section (made of either nylon or a short length of chain) that, when pulled on by the leash, shortens up tightening the collar around the dog's neck, to a limited extent. When properly fitted, martingales are looser than flat-buckle collars when not tightened, and less severely corrective than slip collars when tightened.
It's a good idea to proof your dog's training in different locations to prepare it for distractions. Invite a few friends over to cheer on your dog so it gets used to a crowd. You might also want to go to a training center or find local trainers who also have the obstacles set up in their backyard. If your obstacles are portable, you could even take them to a park.
Remember that training is an ongoing process. You will never be completely finished. It is important to keep working on obedience training throughout the life of your dog. People who learn a language at a young age but stop speaking that language may forget much of it as they grow older. The same goes for your dog: use it or lose it. Running through even the most basic tricks and commands will help them stay fresh in your dog's mind. Plus, it's a great way to spend time with your dog.