Miyamoto, in an interview with Gamepro magazine, gave some really good advice about how would-be game designers should approach a job in the gaming industry:

These days, students may compete with one another on tests and things to see who can get the better score, but you don’t really have a lot of opportunity to create something in school, show it to other people; and then have those people criticize and evaluate your work. That’s something that I think is very important to the game design process. You have to be willing to show a game that you’ve created to other people and then hear their criticisms. Sometimes that can cause a lot of frustration for you. But you have to be able to take that criticism, bring it back with you, and then reflect it in the next version of the game that you make or use it to improve a game you are currently developing. I think that is probably the most important experience that you can build to prepare for a job in video game development.

Great advice Mr. Miyamoto!  And some that I will truly take to heart.

Source: Arstechnica