Job: Tech supportA friend of mine owns a webhosting company, and in college I picked up some shifts as a tech support rep. This was a great job for a student, because the calls were intermittent and I could do it while I studied or did homework.
1 - People can recognize problems without understanding themAs I've covered in another post, game designers need to take every problem seriously.
When a customer reports something to you as specific as "my router is broken," don't get caught up in their theory. If they could tell things like whether their router was broken, they wouldn't need to call you. Focus on the symptoms of their problem, not their theories as to what might be wrong.
If you're more open-minded, you'll be more likely to realize what their real problem is, and if you focus on the router solution, you'll just end up getting into an argument about how their router is working fine.
Same goes for game development: don't focus on what people think the problem is, focus on the experience they are having, and diagnose the problem for yourself.
2 - Small effort on your part can have big results for customersIt's within your power to make people happy, and often you don't have to even go out of your way to do it. As a customer service rep, it's important to parcel out freebies to make up for inconveniences. It's always worth it to give someone a free month of service compared to losing that customer's business forever. It's easy for you, and makes a big difference to them.
In game design, surprisingly small changes can make people happy, be they your coworkers or your player base. Even just giving someone more information can go a long way to making them happy. Make a point to let someone know you're going to fix that bug they hate, and they'll begin cheering up long before they actually see the fix.
Job: Home Depot tool rentalOne of my jobs in high school was working at Home Depot on the weekends. I worked in the tool rental office, where people would come in looking for a metal grinder, floor buffer or generator for the day.
3 - Know your audienceIn the tool rental where I worked, we had at least 3 different levels of each type of tool: Small jobs, pretty hefty, and industrial. All of them worked just fine, but you'd never want to rent someone a 4 inch hand sander if they want to sand an entire hardwood floor, or a floor sander for a furniture building project. One of the most important aspects of my job was figuring out what people needed, and to try and match the right kind of tool to the right kind of job/expertise level of the user.
This is still one of the most important aspects of my job now that I'm a game designer. Almost any design decision is valid under some set of circumstances. Try designing a PvP system without knowing what game it's for. It's impossible to do this well. How central is PvP to our game? What level of expertise does our average player have? What platform is this game for? The ideal PvP system for WoW, Warhammer, Halo, Counter Strike, and Peggle are all very different.
I don't necessarily think designers need things like user stories in every design doc, but take a moment to discuss and agree what kind of game you're making, and for whom.
4 - If someone thinks it's your job, then it's your jobWhen it was time for my lunch break, I had to walk through the whole rest of the store to get back to the break room. Home depot employees all wear the same uniforms, so every day people would stop me on the way to ask me for help. One busy Saturday, I never made it to lunch at all, and after that I had to start walking around the outside of the building.
If you're a game designer, people outside of your discipline don't understand or care about the difference between a content designer and a combat systems designer. They just know there's a bug that needs to be fixed. It's your responsibility to either fix that bug or direct them to the person who can. There's no such thing as "not my problem."
Job: Various sales shillsI spent some time selling ad space in local newsletters, ad space on diner placemats, and pages in those crappy coupon books high school students are always selling. I also was one of those annoying high school students selling the books. Being a salesman was my least favorite job ever.
5 - High rewards are more motivating than low costWhether you're selling something, convincing an engineering team to implement a feature for you, or designing reward systems, bang for the buck is what counts. Even if something only costs a dollar, it has to be worth more than a dollar or people won't want it. Not to mention the fact that cheap things are actually seen as less desirable to most people. Strangely, the easiest way to sell something to people is to charge them double what it's worth, but convince them that it's worth triple.
This also has implications for your career and writing resumes. Game design is a very subjective and often squishy discipline, but it's important to find ways to measure your success so that you can make people see that you're good at your job.