I've personally raised and hunted with 4 different hunting dogs. And the most important and first command to teach them is the "woe" command. This command is critical, as it is the command that tells them to immediately and completely cease what they are doing, stand still, and await the next command. For a hunting dog, and as a general command with house dogs, this command can save their life when in the field by stopping them from running into the line of fire, or prevent them from running out into a busy street, because it immediately stops them in their tracks. A hunting dog that doesn't know or respond to a woe command will be a very difficult hunting dog to keep control of when control is needed most.
It can be given with different terminology, but it should be noted that what ever word you apply to this command, it must be something that can't possibly be confused with any other command. An example of the wrong words for this would be one that sounds similar to the intended command, such as "no" and "woe", see what I mean. It should also always be a one word command, so it can be delivered with an abrupt, and impossible to confuse tone.
As for gun breaking them, this is a controversial area. Some say start them as pups with fire crackers, or starting pistols during feeding time. Others say that gun breaking them any younger than 1 yr. old is a bad idea, as there is too much risk of them being so traumatized by the noise, that they may never get over it. I've tried both methods, but I did have one dog that I thought I had ruined by starting at too young an age. He did however recover and become a good bird dog, but it was a close call.
The same controversy exists regarding when to start teaching field commands. Some say let them be puppies for the first year, and get it out of their system. I did just that and found that and allowed them to mature a bit before teaching any field commands. I did teach basic obedience, this is important, but don't cram it down their throat when they are still puppies. Too much obedience while in their puppy years can effect their spirit and turn them into a cowering pet unwilling to anything. for fear they will get punished, It can also make them think they must get a reward or treat for every command given, you don't want that to happen.
I strongly recommend reading a good book on this though. Two such authors that helped me a lot were written by DL Walter's, and Larry Mueller. Both of those authors use some very basic, yet innovative methods of conditioning and advanced training drills. It's been a long time since I worked with dogs at this level, but those two trainers really helped me a lot.
One little tip if you have children though. Don't let them chase your dog as a puppy, this causes serious problems later on, or when the time comes to start their training routine. The last thing you want is a hunting dog running from you, or thinking that you want to play with them when giving a command.
GS