Before you start - birds and more birds. You need the dog to be bird crazy and then it will be much easier. At around 4 months of age (differs in each dog) you'll start noticing things like the dog is staring at faraway birds or it starts stalking robins, etc. That's when you introduce birds and the gun.

First, weigh a bird (pigeon, chukar, or quail for a small dog) down by tying a thin rope attached to a piece of garden hose. Or just tie a rope with you holding the other end. Let the dog go at it.

After awhile, you can shoot a starters pistol right when the dog is just about to grab it. Watch the closely. If it shows the slightest reaction, put the pistol away and do it again the next day. Let the dog play with it some more. If no reaction, you can fire a few times more. A couple outings then graduate to a smaller shotgun or louder blanks. I used a H&R .410 bought from Walmart for $120. Repeat the process. If you think the dog will flinch then have someone else fire the gun at around 100 yards away. Then slowly come closer and closer.

Then for the first season, you should only hunt with the dog alone so it can get use to gun shots. Put too many guns on an unconditioned dog and it may become gunshy.

I don't like banging pots and pans. 90% of a dog's learning comes through association. Banging pots and pans only allows the dog to getting used to loud noises. You want the dog to associate gun shots with birds. I perfer to control where and how the dog makes that particular association and not letting the dog figure it out themselves. Too many things can go wrong. Also, I do not like taking a pup to a firing range. Too many guns going off at once and you can't get away fast enough. Sometimes rifles ranges are next to shotgun ranges and Hi-powered rifles are very hard on a dogs ear. Hi-powered rifles are in the super sonic range (shotguns are sub-sonic) and because of the doppler effect creates a mini sonic boom (pressure builds up). That's why it hurts your ears when bench shooting.

Here is a video of a professional trainer, Keith Hickem, using a dead pigeon to make a pup go bird crazy. Towards the end, he shoots a starter pistol but watch his timing of when he shoots.

http://www.youtube.com/watch?v=xYm5aBuJd4M&feature=related