How to Prototype a Game in Under 7 Days

Brilliant in it's way - choice pieces include:

"If You Can Get Away With it, Fake it

This is arguably one of the most important lessons of the project. Often the “correct” solution is not the best solution. Strategically faking it will save you time and money; it will make your game faster, and your teeth whiter. Fake it liberally and often! ... This rule is also a fantastic general lesson for life, we have found. Slackers, take note."

"Heavy Theming Will Not Salvage Bad Design (or "You Can't Polish a Turd")"

self-explanitory, I think.

"Build Toward a Well Defined Goal

A well defined goal was embarrassingly easy to forget about. Without a gameplay goal, a prototype is just a toy – not a game. For some reason, people seem to enjoy having the opportunity to fail. A goal can be anything..."

and

"Our objective advisor kindly pointed out, “Rapid prototyping can be a lot like conceiving a child. No one expects a winner every time, but you always walk away having learned something new, and it's usually a lot of fun!”"

Check it out:

http://www.gamasutra.com/features/20051026/gabler_01.shtml