From IBM developerWorks:

Adopt 10 good habits that improve your UNIX® command line efficiency -- and break away lrom bad usage patterns in the process. This article takes you step-by-step through several good, but too often neglected, techniques for command-line operations. Learn about common errors and how to overcome them, so you can learn exactly why these UNIX habits are worth picking up.

Read the full thing at http://www-128.ibm.com/developerworks/aix/library/au-badunixhabits.html?ca=dgr-lnxw97TenUnixTips

I have to admit, there where a couple of 'do nots' that I am guilty of doing....