Time management. I've worked engineering jobs, and I go to an engineering school, I work a research position, am part of an enterprise where we are building a hybrid electric 1950 Chevy Pickup, I am working on a senior design team where we are building adjustable height suspension, and I am a team leader in my enterprise so I have to organize projects for my team and help them, attend many meetings. I stay busy, but I also manage to have time to go skiing, snowmobiling, motorcycle rides, parties. All this on top of my classes...
I have friend's who are in similar situations with a slightly lower work load yet they always complain about being too busy to do anything. The reason I have time for the things I enjoy, when I want to is because I balance my schedule well. I am efficient and always try and produce quality work.
So I guess that's not really my way of handling stress, it's more of a way of avoiding it in the first place.
And the working world is a little easier in fact, unless you let your boss take advantage of you. I've worked for GM (engineering), an Oil Refinery(engineering), on a farm, in a school tech department, Americorps... One thing was the same in all of them. You put in your hours, and when you go home, you are free to do whatever you like. I loved that. Sure there are long days, but if you constantly are having long days, then you are either: A) being taken advantage of. B) making bank overtime. C) Not working efficiently enough D) You really love your job so you don't mind.