About Eight Golden Rules

1. Strive for consistency.

Try to make it so the user intuitively knows what to do because they’ve seen the same situation before throughout your interface. This means making terminology the same throughout and making sequences of actions be the same in similar situations. A good example of this is Mac’s operating system OSX. Everything ties into one another. Their progress bar has the same look and feel as a program window. Any confirmation windows always have an ‘ok’ and a ‘cancel’ button. This holds true for pretty well every  operating system out there.

2. Enable frequent users to use shortcuts.

Make it so the user doesn’t have to work so hard to get from point A to B. This is especially valid for users that use the interface on a regular basis. Somethings to consider might be, abbreviations, function keys, hidden commands and automated actions. Yahoo mail does a good job of this. You can press a letter like ‘n’ to start a new message, or ‘f’ to forward a message.

3. Offer informative feedback.

For every action that the user does, there should be some sort of feedback, either good or bad. For more frequent and minor actions the response can be minimal. For infrequent and major actions the feed back should be more substantial. I’ll use Yahoo mail as an example again. If you try and enter a bogus username or password, it gives you feedback letting you know why you couldn’t log in.

4. Walk user through more complicated tasks.

When you have an action that requires several steps, be sure to separate it into a logical beginning, middle and end. After each step be sure to give feedback that will clarify that the step was done correctly and they can move on to the next step. At the end of all the steps be sure to let the user know that they are completed and that they have finished all the requirements. An example of this might be an installation wizard on your operating system, or any checkout shopping cart on the web.

5. Offer simple error handling.

As much as possible, design the system so the user cannot make a serious error. If an error is made, the system should be able to detect the error and offer simple, comprehensible solution for handling the error.

6. Permit easy reversal of actions.

Give a way for the user to undo an error. This will help keep the user at ease if they know that not everything has to be perfect. This will encourage further exploration of your interface. You might want to place an undo feature when dealing with a single actions, a data entry or a complete group of actions. Any word processor is a good example of this. Ctrl + z is probably one of the most popular key commands out there.

7. Make the user feel in control.

Experienced users always want to feel like they are in control of the system. Make sure the design makes the user feel in control and not just responding to a situation. iGoogle does a good job of this. They allow users to customize their workspace, and put only what they want up front.

8. Keep it simple

People have a limited short-term memory. Having to keep track of several things at once can leave a user frustrated or incapable of using your interface. Try and consolidate multiple pages, reduce unneeded motion, and generally just keep things simple. This will go a long way to help your user’s frustration level. Again Google nailed this. What’s simpler than a text box and a button?

source : http://www.devirtuoso.com/2009/05/8-golden-rules-of-interface-design/