Do's and don'ts in web design

DO plan ahead
People think of different things when they hear "web design." Some put too much weight on the word "design" and forgetting "web" - but a site can look great and still be a failure if it doesn't work. Remember to plan how it should function, as part of the content.
DO make it quick
If your site is slow to download, your visitors will most likely leave - especially if they don't know what the site is about. Remember, the rival is only a click away!
DO appreciate textual content
It's only in rare cases that the design is more important than the text - like when the point of the site is to show the design itself. In all other cases, the design should only be used to support the content; what visitors come to read.
DO learn HTML
Or these days, XHTML or XML. Why would you need that, with all the visual editors available that hide the code for you? Simply because while these tools may help you very much, a human is able to write better HTML, and will be able to clean up what the visual editors may create.
DON'T think you know it all
...because no one does. There's always something new to learn for anyone.
DO start your work on paper
Sketching on paper how you want your site, with all the pages in relation to each other and the best and easiest way to navigate them. Then you can start the computer work.
DO check the spelling
Nothing makes the content appear worse and amateurish than bad spelling. Check and correct any mistakes before you publish.
DON'T annoy your visitors
Certain tricks has always been used to attract the attention of the visitors. Gif-animations are one thing, the dreadful tag another. But while the movement and blinking attract the attention, it also turns visitors away - because the annoying elements breaks their concentration.
DO be careful with fonts
Too many fonts looks bad. Too small fonts look bad - and the same font and size do look very different on different computers and resolutions. What may suit you may be too small for many. And when you set a font face, remember to provide alternatives, including the generic 'sans-serif' or 'serif'.
DON'T use wild backgrounds
To make it easy for visitors to read your content, make the contrast between the text and background good. Patterned backgrounds under the text will make it hard to read, and some colours don't go well together.
DO save often
And do keep backups.
DON'T confuse visitors
Make navigation simple and logical. Let them know where on the site they are.
DON'T regret
But do learn from your mistakes. There's bound to be mistakes, and things you would do better given a second chance.
DO listen
When people tell you they don't like your site, do listen to them. You may disagree and be right, but try to understand why they don't like it - you can learn a lot from it!
DON'T use frames
Frames are out now, a thing of the past. To display pages with frames, you really need a large monitor, bookmarking is difficult or impossible (especially if you want to send the URL to a friend) and much more. Search engines often get confused by frames, and won't list the site - you don't want that?
DON'T be harry
Using techniques for their own sake is a miss, and it won't impress anyone that aren't looking for exactly that thing - and then only once. Do you have a flash intro? Make it possible to skip it.
DON'T limit me
Making a site dependent on particular plug-ins reduces its appeal, and the number of visitors willing to spend time on your site, particulary if they have to download the plug-in. They may not come back.
DO provide alt-texts
Even people with ISDN connections turn off graphics to get better performance, in addition to blind and sight impaired users.
DON'T break copyrights
If you haven't made it yourself, and haven't got permission from the author/artist, don't use it on your pages. If people will be flattered to find their work copied and used, it will be possible to contact them first and make a deal - legally.