How can you control your undesired feeling expressing to others?

Normally, my eyes are big which make other people
think that I angry at them. Especially, when I feel bad or
irritated with something that I did not know how fierce my face is,
it makes others following get bad together.
Anyway, I try to smile when I figure out that I am being angry,
I won't be beautiful.. Let's smile.   
Just smile, everything is going to be alright.   
No one can take over everything. We don't posess this world.
We are one importanct thing which fulfill our world.
That's all about techniques how to control my bad feeling.   
Sayumporn 065 3EN