So in todays tournament I was a poor sport to my opponent (a long time friend) and I'm really unhappy with myself about it. I gave him the 10-0 at the end (he won anyway, but I wanted to apologize and it was only a three person tournament so I didn't feel I was upsetting the rankings much), but I want to take steps to cure myself of that kind of behavior in the future.
If you catch yourself doing bad sportsmanship things, or having had sportsmanship thoughts, etc. What do you do? How do you bring yourself under control in the heat of the moment?