What are some important qualities of a good supervisor (boss)?

Can someone help me check my essay? Thanks in advance ^^

I'm going to sum up three vital qualities a supervisor must possess.

Firstly, a supervisor must be kind-hearted, slow to anger, and stern if need be. Kind-hearted, as in to treat his employees well. A supervisor must know how to separate personal problem from work, and not take his personal problem to the office. He mustn't let his anger get the better of him. Just because he's a boss, doesn't mean he can lash out at his employees whenever he feels like, because that's surely not a quality of a good supervisor/boss. Stern if need be, point in case, if we bump into each other on streets, he would deign to offer a smile, but be stern at work, so as not to encourage his employees to take their works lightly and disrespect him.

Secondly, a boss must put aside his status and not set his mind into thinking that he's above all his employees. He should try to befriend them as opposed to just order them around. Rather, try to see things from their insights and heed their advice instead of imposing his own opinion on his employees. He should try to build a good relationship with his employees based on trust. Truth be told, the only way he can get them to respect him, is earn their respect and trust. Therefore, he should.

Last but not least, leadership and be an expert in his field. That is how he can get people to follow him. Rudely speaking, if you have an imbecile for a boss, you would more likely suck up to him in front and insult him behind his back. In a nutshell, no one respects that kind of boss. Instead, show them he's capable of leading. Impress on them the importance of co-operation between co-workers in order to obtain a better performance. Ascertain that each employee takes their job seriously and encourage the good relationship between co-workers.

What do you think of it? Note that English is not my mother-tongue
I know i need to work on my vocabulary
Include advice and critics to help me improve, if you would ^^

Is this for a writing task or a speaking task? ... Whatever it is, I'd suggest you to include just one line to introduce who a supervisor is. Something like;

Supervisor is the person who monitors and regulates his subordinates. In my view, an effective supervisor needs to have ????????? (list the qualities)
Then dedicate each paragraph to talk about one quality. Give examples to support them.

secondly change into in additon, better, but not important

Rather, he should try to get the subordinates involved in decision making by consulting their ideas and opinions instead of being rigidly trying to impose his own opinion on them.


...this is confusing;
A leader should display his expertise in his field. This helps him not only to win confidence of subordinates, but also to earn admiration by them.