I. Thou shalt respect thy user
It is paramount that you respect the user and their data. Don't steal their MP3s, don't look at their porn. When working with email, look without reading. Respect them and they will respect you.
II. Thou shalt empower the user
The user is the customer. The system is not yours, it is theirs. Provide users the tools they need to be successful and they will be happy. Give them space to experiment, learn and create. Do not hold users back.
III. Thou shalt keep it simple
Keep It Simple, Stupid. The KISS principle will keep you from building barrels to keep a bottle's worth of wine. Do not mistake over-engineering for quality. Quality work is concise and scalable.
IV. Thou shalt expect catastrophe
Expect the worst surprises. Make your resources redundant, backup your data, test your backups, and then backup the backups. The shit will hit the fan someday. Be prepared.
V. Thou shalt plan
Great work follows great plans. Stay on target by first identifying it. Plan your work carefully and surprises will be easier to handle.
VI. Thou shalt stay informed
Gather all the news, information, logs and statistics you can. Without the raw data to analyze, you cannot debug problems and you cannot forecast. Without new information, you cannot learn.
VII. Thou shalt share
No one is alone in this world. Pass your knowledge on to others. Give to others, contribute to the community and you will reap many rewards. It is not wise to horde knowledge. Don't be an asshole.
VIII. Thou shalt automate
Do more, faster by automating tasks. You are the puppet master, do not waste your time with menial work. Work smarter, not harder.
IX. Thou shalt document
Always document your work, your code and your plans. Then document their execution and maintenance. Document for others and document for yourself. Documentation should be an extension of your mind and a resource for others.
X. Thou shalt respect thy organization
Without organization, there is no system, there is no user and there is no job. Understand the organization and its business. Respect it and help it thrive.