To see an example of all the unlucky seven in one place try this link.
The *blink* technique is most commonly used by banner advertisements to catch and hold your attention. Designers sometimes use it in a Web page's content section to draw attention to important text. But beware. Often, the animation draws so much negative attention that visitors leave your site immediately and never see that important content.
Use larger headings and bulleted text instead of blinking animation to emphasize important section
Some designers get so excited and bewildered by the variety of fonts and colors available that they have a hard time choosing the best ones. So they compromise and use them all. The end result often resembles a ransom note cut from several different magazines.
Ransom note text takes forever to code by hand since each single letter has a different font and color. It's easier and more tempting if you're using a WYSIWYG editor because you don't have to write the code, just point and click.
Resist that temptation! Use common fonts (Arial, Times Roman, etc) because all browsers recognize them. All the time you spend optimizing your layout using the Showcard Gothic font (for instance) will be wasted if your visitors' browsers don't recognize it and instead default to Times Roman.
Few Web sites are static. Most are continually being updated with new information and optimized for search engines. In a sense, they're always "under construction."
However, that message should never appear on your home page because you're essentially telling visitors that your site is a waste of their time. Never submit to search engines until the site (or at least the home page) is complete. If you have some sections of other pages that aren't complete, it's ok to note that, but avoid the animated road construction graphic.
Few statements on a Web page annoy visitors as much as this one. Think about it: have you ever downloaded a new browser (or browser version) just to look at a single Web site? Unless you are absolutely certain that visitors will use a particular browser (on a company Intranet, for example), all sites should be optimized to display effectively across browsers.
Background music on a page adds no content but increases the annoyance factor - and the page download time. It's ok to include music clips on your site, but give your visitors the option to listen instead of assaulting them with a tinny rendition of Beethoven's Fifth Symphony the instant your page loads. The choice makes your site seem more interactive and gives visitors more control of their experience.
Horizontal scrollbars decrease a page's usability because visitors have to manually scroll the page back and forth to view the content. Monitor resolution settings can cause a Web page display to look drastically different from one monitor to the next. Visitors with low resolution monitors are most likely the ones to encounter horizontal scrollbars.
Remember: if you designed your site with your monitor display set to 800x600, your Web page will appear 20% larger (and fuzzier) on a 640x480 monitor. Most Web designers have 17-inch monitors set to 800x600 pixel resolution (or higher) and tend to forget that the rest of the world is not quite so lucky.
Ideally, you should test your site on a variety of different monitors, but that can be difficult if your only access is your home or office PC. At least adjust the settings on your own monitor to see how your page will appear at different resolutions.
The Web Palette consists of the 216 colors that both Macintosh and Windows systems display accurately. Here is another area where color can get you into trouble. Many of those 216 colors aren't found in nature - and shouldn't be on your Web site either.