Always make sure when you put your decoys out that you keep the anchor strings as short as possible or the dog will get tangled in your decoy spread and start dragging them around. A young dog can become afraid of a floating decoy if he has become tangled in the anchor string and the decoys bumps him a few times. We don't want that.
Many dogs don't hear a duck or goose call until the first time they hunt. When they do, they can't identify the noise and it causes excitement and confusion. You need to condition your dogs to the call. Use the call while you're training them.
Many dogs have never been shot over prior to their first hunt. You have to train the dog to react positively to a shotgun going off over his head. In training, start out shooting away from the dog and slowly adjust until you are shooting right over the dog. You want the dog to remain perfectly still as the gun is going off.
What I do when training is blow the call for a while, shoot the gun and throw the dummy bird to retrieve. Then the dog will get used to the scenario. He'll become more efficient when he's not surprised and will perform properly that first time in the duck blind or the boat.
If we're going to change something - let's say we've been hunting out of a blind and now we're going to use a boat - then we should expose the dog to the boat and make him comfortable in it before we hunt.
I never get too critical of my dogs in a new situation until they know what is expected of them. Once they understand the rules, then often just a low level of stimulation from the collar is all that's necessary to keep them on track.
Bad habits are reinforced every time we let a dog do something more than once. If you let your dog leave the boat or leave the blind before you have commanded it, then you are allowing a situation to develop that will be harder to break later. That's why you want to have all the kinks worked out before you actually enter a hunting situation.