I am lucky. I work at a school, that so far, has backed me in the issue of discipline. I've kicked kids out of class when they misbehave, and I've not been admonished for it. All the teachers see what I do. I've had students clean the black board or write ten times on the board such silly things as "I will not eat a hamburger in English class." It's all about making them lose a little face in front of their friends. It's not a psychological or emotional trauma they can't bounce back from later.

I only kick them out for a few minutes so I can talk to them later about behaving better. I've deposited some students at their head teacher's office so they can help with the cleaning.

It is not so much that I instill a great sense of fear in them. The key is to remind them that if they do not listen to me, they can talk to their head teachers after class about it. And yes getting very near (in their face) to a student helps in calming them down, as I've said before.
I've even put one class under Marshall law where the head teacher sat in the back for two weeks.