Before we get into self-defense strategies, let's clear up some common misconceptions about bully bosses.
Myth: It's a good idea to confront your bully so he sees that you're not afraid.
Truth: Personal confrontations with bullies are almost never productive.
Myth: The first thing an employee should do following a bullying incident is talk to management.
Truth: Management team members interpret any confrontation an employee might have with a boss as also being a confrontation with them, and without well-documented proof of a pattern of behavior, they will likely view the employee as the problem.
Myth: You should avoid your bullying boss whenever possible.
Truth: If bullies notice you're ducking them, they will not see this as sensible avoidance, but as cowering behavior.
Myth: Don't look a bully right it the eye. It's provocative.
Truth: On the contrary. Maintain steady eye contact. If too difficult, then focus between his/her eyes on the bridge of his nose. One bullied employee even removed his Coke-bottle-thick glasses before a meeting so he maintain direct eye contact with his boss without feeling intimidated.
Myth: Get personal with a bully to diffuse some of his or her anger, and to show him your human side.
Truth: Bullies not only don't do the personal, most don't tolerate it in others either. Details of your personal, spiritual, or emotional life are weapons in your antagonist's hands.
Myth: Seek help from the company's HR department. That's what they're there for.
Truth: HR can be the chilliest place any employee can visit, and also one of the most dangerous. HR's allegiance is to the employer--and protecting the employer from legal claims. Approach rarely, with caution, and only when fully prepared.
Myth: It's good strategy to relate your story to as many coworkers as possible, right after an incident, if possible.
Truth: Unfortunately, your story has a negative emotional quality that can repel listeners. Allies must be identified and groomed carefully before you enlist their support. Moreover, it's better to be circumspect about sharing your story--write down detailed notes about it first. You can present it in a more organized and effective way later, when the timing is strategically advantageous.