Here's a thought - if you get frustrated, try 'shaking' yourself before you interact with your dog. The body shake is something dogs often do when they switch from an excited state to calm one. Obviously, you're not a dog, and you probably can't shake like a dog, either, but dogs are pretty good about translating behavior signals. A quick head-shake might help let your dog that even though you were upset before, you're not anymore, and now it's ok. The downside is you look like a complete idiot if you try it in public (but not as much as the time I instinctively started yelping in the elevator to teach a puppy bite inhibition. I sounded like Beaker).
For me, controlling my body language is the single hardest thing about dog training. Dogs notice the thousands of little things in your behavior that you never even thought of - which direction your feet are pointed, whether your shoulders are tense or relaxed, how far your knees are bent, whether your weight is shifted forwards or backwards, whether your pupils are dilated - and will probably interpret them correctly. I have distinct memories of my comical attempts to seem excited and happy that my dog was pooping outside at 3AM in subzero weather. I doubt my dog bought it, but I think she appreciated the effort.
This sounds weird, but the best way to control your body is to approach it like an actor. The American 'method' style of acting is about harnessing your emotions to influence your body language - get control of your emotions, then let that direct your behavior. The British style is the converse - control individual elements of your body to invoke an emotional response. Generally, people will find one style comes more naturally to them than the other, but the effect is the same - you need to figure out how to signal your dog that 'Everything is ok' without using your voice. Eventually, you find yourself doing it all the time, instinctively - and your dog will start acting that way, too. I've never acted a day in my life, but I find that it works.
For me, controlling my body language is the single hardest thing about dog training. Dogs notice the thousands of little things in your behavior that you never even thought of - which direction your feet are pointed, whether your shoulders are tense or relaxed, how far your knees are bent, whether your weight is shifted forwards or backwards, whether your pupils are dilated - and will probably interpret them correctly. I have distinct memories of my comical attempts to seem excited and happy that my dog was pooping outside at 3AM in subzero weather. I doubt my dog bought it, but I think she appreciated the effort.
This sounds weird, but the best way to control your body is to approach it like an actor. The American 'method' style of acting is about harnessing your emotions to influence your body language - get control of your emotions, then let that direct your behavior. The British style is the converse - control individual elements of your body to invoke an emotional response. Generally, people will find one style comes more naturally to them than the other, but the effect is the same - you need to figure out how to signal your dog that 'Everything is ok' without using your voice. Eventually, you find yourself doing it all the time, instinctively - and your dog will start acting that way, too. I've never acted a day in my life, but I find that it works.