Under construction signs
    It's beyond me why some people use those 'under construction' signs on their sites. If a page is not ready, don't put it on the web. Would you buy a book if it says on the cover: 'under construction: last chapter not yet written'? Would you buy a car if the manual said 'under construction: brakes have not been installed yet'? So why would anyone even consider looking at a webpage 'under construction'? Don't worry: they won't.
Only put on the web what is finished.

Incomplete sites
    Every now and again you'll find a site with a very promising home page. But almost everly link off it just shows an empty page, saying: this section is not yet ready, please come back later. No one ever will. Remember Garth: 'If you build it, they will come...'

Make only links to finished pages.

Promises, promises
    Sometimes you find a site promising a new section, supposedly the best of its kind. You come back a month later, the promise is still there. The section isn't. Yet. Same next month. A month after that you finally find a lame excuse for a page that leaves you puzzled. Tant de bruit pour une omelette? Please take me away from here!
Make only promises you can keep.

Superfluous pages
    The main function of the web - if not the only - is information. Your visitors are hungry for knowledge. If they want to be entertained (or bored), they watch TV. So why do I keep seeing all those 'flash' pages, or sometimes even complete self loading slide shows? What a waste of time and energy.
Make only pages containing information.

The latest thing
    There is a strange fascination about new gadgets. Everyone seems to want to have and use them. Without ever wondering if they're usefull or necessary or just plain stupid. Standards are rapidly changing on the web. New gadgets pop up every day. JAVA, javascript, jscript, style sheets, vbscript, VRML, XML, XDFL, SMIL, animated gifs, frames, embedded sound, movies, plugins, the list seems endless. Some of them may be usefull. Sometimes. Most of them are not.
Use proven techniques, viewable with any browser.

Best viewed with...
    If I need a special browser or plugin to view your page, it shouldn't be on the web. It simply clashes with the essential strength of the web: independence of operating systems, server technology, software, file formats and the lot. If only the latest and greatest browser will do, most people will never see your page. Or do you really think anyone will download and install yet another 20 MB monster, just to see your page? Get real.
View your site with a previous generation browser.

World Wide Wait
    Try holding your breath for as long as it takes your page to load. Suffocating yet? Then your page is way to long. An average page shouldn't take more than twenty or thirty seconds to load, or be 50 kiloBytes max including images. At least something should be visible right away. If not, the majority of your visitors will be long gone, looking for greener pastures.
Try to keep your pages under 50 K max.

Animated GIFs
    Animated GIFs attract attention. AWAY from the page. Many animated GIFs just divide attention. Most graphics are large files. Most animated GIFs are very large files. Is the animation the main thing on your page? Then use it. If it's not: DON'T.
Only use animations if absolutely necessary.

JAVA
    Once this was the 'next big thing'. Interactivity and portability at long last. Indeed they are very big things. Small ones are just gadgets, big'un's may be usefull but take forever to load. Not to mention they often crash browsers (Oh no, not again...). Most interactivity can just as easily be accomplished with a few lines of PERL or PHP at the server. So why use JAVA?
Use CGI for interactivity.

Javascript
    Another 'next big thing', but maybe one to stay. Maybe. Being much smaller than JAVA and therefore more usefull. So it is probably suitable for interactivity purposes, like form checking. But more often used for annoying gadgets, like scrolling status bars. Sends shivers down my spine, just thinking of it.
Only use javascript if absolutely necessary.

WYSIWYG editors
    A contradiction in terms: what you see in your editor, is NOT what you get in your browser. Different browsers will show the same webpage differently. The language of the web is HTML. So use it. WYSIWYG editors don't produce HTML. They produce garbage.
Learn HTML and use a plain text editor.

Background music
    Background music? Or background noise? Just because you CAN use it doesn't necessarily mean you HAVE to. It just reminds me of being put on hold by a telephone operator. You just have to listen to those rotten tunes, just in case you get the connection you want. If I want to hear music, I turn on my stereo, my tv, or even my old portable radio, but most certainly not my computer. Or it must be my own MP3 collection.
Just make great pages. Then you don't need sound.

Counters
    Very annoying are counters on web pages. Consider this: you don't put a sign by your front door telling how many people have visited your house. Then why on earth would you do this at your home page? Don't put a counter directly on your page, use a hidden counter. If you would like to track your visitors a bit, you click the icon.
Use a hidden counter.

Banner ads
    Beware of using banner ads at your site. Especially javascript driven popup windows are considered very annoying by the majority of web surfers. I won't even talk about those exit popups, that keep dragging you back to the site you just left. Consider this: how often do you click a banner? Is it really worth wasting the bandwidth? Or to annoy your visitors? If so, use them, sparingly. If not, get rid of them.
Only use banner ads if you really need them.

Advice blindly
    There are a lot of sites out there - not unlike this one - telling you how to make a site. Each one may tell you a different story. So how to decide what advice to follow? Well, that's for you to find out. If you like this site, great. If you don't, that's cool too. Just don't follow advice blindly. There's always more than one way to do something. At least read several sites or books on web design, find out what you like. Maybe even more important, what you don't.
Find your own way.