Approaches to design

A design approach is a general philosophy that may or may not include a guide for specific methods. Some are to guide the overall goal of the design. Other approaches are to guide the tendencies of the designer. A combination of approaches may be used if they don't conflict.
Some popular approaches include:

User centered design, which focuses on the needs, wants, and limitations of the end user of the designed artifact
Use-centered design, which focuses on how it will be used with less emphasis on the user than user-centered design
KISS principle, (Keep it Simple, Stupid), which strives to eliminate unnecessary complications
There is more than one way to do it (TMTOWTDI), a philosophy to allow multiple methods of doing the same thing
Murphy's Law (Everything that can go wrong will, so plan for it beforehand)

for more details - http://en.wikipedia.org/wiki/Design