You need to keep in mind that in training your dog, mistakes come along the way. Mistakes always happen and it is part of the learning process.
Mistakes happen during dog training
Be patient with your dog
Learn from previous mistakes
Both you as a teacher or your dog will make a mistake sometime during your training. Each mistake gives valuable information. When you know what caused the mistake, you will less likely to repeat it again.
There is no need to make a big fuss about it. Just go on with your training session like nothing happened, and make sure that you won’t make the same mistake again. There is no need to treat your dog harshly to help him learn from his mistakes.
Learn from your mistakes, since that is one of its purposes. Once mistakes are identified and corrected dog training will become faster and successful.