What to do when I am upset

First of all
That feeling won't stay forever.
I know you're upset now, but just know you're not gonna feel upset or angry forever.
That's the first thing to remember.

Then, this is what works for me
I go to my room to cool off
Watch some good TV or a movie, comedy perhaps.
accompanied with some good food
(just don't make snacking as a solution for your problem)
Eat Fruits instead ;p
After 30 mins or so,
I'm all better.
Really, no matter how upset/angry I felt earlier, I'm now calm and happier.

Give it a few more hours and I start to think straight
and I see how unnecessary it was to be upset in the first place.
I learn if I could just let it go, I didn't have to feel upset at all.
I could just let go and move on and be happy.