I find that getting mad happens when you play a game often. If you play something a lot you have expectations on yourself and get pissed when someone trumps them, but if you don't play every day you just accept that there are people who are a lot better than you. I'd rather get my ass kicked here and there and not really care than lose my shit when someone beats me.
OooOOOoh he's got it right. I know what you mean man, happens to me too. What got me over it was just messing around for whole matches with my friend playing games just to mess around. Helps to not take things too seriously.
Got it when I was 18. Wasn't too hard but that's cuz I studied off a BUNCH of peoples old test. If you can I'd get a hold of peoples old test to study off of. Uhh... from what I can remember avoid puddles, finish crossing intersections no matter what and always inform the DMV about your cars.