Here are Some quick tips to know if you want to be a good site designer.

Learn html,php and other web making language.

Know more about colour combination and lay-out.

Creat your site with low animation and loaded with interactivities like poll and rating.

If you want to learn more about web language then visit this site: www.w3schools.com

Ok, that was nice but i would like to add something more.
To be a good webdesigner, one should be creative while considering the target audience and it's requirements.
There are so many templates available on internet, inspiration from them and everything around us will help us to lead the design world.
For more you can check tutorialized.com, templatemonster.com, thetemplatestore.com or even can try with some free templates to get the feel what's in and out

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I agree.. Focusing on your customers definition of SUCCESS while adhering to W3C standards and technical nuances. Web Project Management.

Know how to learn. Learn how to learn. Critical skills because, as you are already aware, new technologies are constantly being introduced; you need to keep yourself up to date.

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online.education

Learn , learn and learn again !
And when you think you know all that you need look for something new ( because all the time is something new to learn in this domain )
I agree with you all 100% !
But you have to put "youre hand" there too !
You can learn , learn and learn but you also learn many things from youre mistakes
Also you need to like what you are doing ... because if you don`t like what you are doing and you make it just to make $ out of it you will not be a great designer/programmer !

The rest is up ! Or allmost thate essential !

in reality, every career doesnt really require you to be all expert. becoming expert needs experience -- but you wont have experience if you dont do jobs. its a chicken-and-egg situation.

I agree with most of the hints shown here. I'd like to add another key hint that few have the courage to take into account. "Experiment, don't be afraid to try something new". Like that you will learn, get unique designs and NEVER forget what you have discovered.

All in all, a good website designer should focus on the visitors' needs; how fast the page loads, how easy their navigation on your site will be, how easy is for them to find what they want, will the color scheme you use hurt their eyes, etc.

Its not all about knowing languages.You should also be a bit creative about your site design.Your site should have a good look that can bring more visitors and also try to keep other things that would keep visitors busy.

There are many templates available online and you can also use tools like dreamweaver and frontpage to design templates.Also try to give a good logo to your site by photoshop.