There's a great post on Design Observer that I've just found even though it was written in March 2004.
It's called Ten Things They Never Taught Me in Design School and it's facinating. I'll list the ten below, but it's worth clicking through to read the little justifications.
1. Talent is one-third of the success equation.
2. 95 percent of any creative profession is shit work.
3. If everything is equally important, then nothing is very important.
4. Don’t over-think a problem.
5. Start with what you know; then remove the unknowns.
6. Don’t forget your goal.
7. When you throw your weight around, you usually fall off balance.
8. The road to hell is paved with good intentions; or, no good deed goes unpunished.
9. It all comes down to output.
10. The rest of the world counts.
My favourite is probably number 5. Start with what you know; then remove the unknown.
"In design this means “draw what you know.” Start by putting down what you already know and already understand. If you are designing a chair, for example, you know that humans are of predictable height. The seat height, the angle of repose, and the loading requirements can at least be approximated. So draw them. Most students panic when faced with something they do not know and cannot control. Forget about it. Begin at the beginning. Then work on each unknown, solving and removing them one at a time. It is the most important rule of design. In Zen it is expressed as “Be where you are.” It works."
This all seems like good advice for the Design is the New Management Consultancy stuff.