If it is something personal I get in the car drive to an empty street or area and scream at myself at the top of my voice. 

 Then a little role playing to encourage all my positives and to forget my lackings. 

 

Like if my boss was kind of bad to me today. I wud drive to the road opposite the parking behind Bidda park or the parking lot of the park near Doha club and shut myself in well and scream at myself. At some point there wud be tears in my eyes due to the effort and muscle involved. Thats when i have to stop. Then till i get home i make up a conference of my own to congratulate myself for all my achievements, discuss what is wrong with the system and visualize kicking my boss in the A**. When I get home if the minus mood still remains, then I have an old Tennis racket that I'm trying to bend.