When it comes to your website, extra attention should be paid to every minute detail to make sure it performs optimally to serve its purpose. Here are seven important rules of thumb to observe to make sure your website performs well.

1) Do not use splash pages
Splash pages are the first pages you see when you arrive at a website. They normally have a very beautiful image with words like "welcome" or "click here to enter". In fact, they are just that -- pretty vases with no real purpose. Do not let your visitors have a reason to click on the "back" button! Give them the value of your site up front without the splash page.
2) Do not use excessive banner advertisements
Even the least net savvy people have trained themselves to ignore banner advertisements so you will be wasting valuable website real estate. Instead, provide more valueable content and weave relevant affiliate links into your content, and let your visitors feel that they want to buy instead of being pushed to buy.
3) Have a simple and clear navigation
You have to provide a simple and very straightforward navigation menu so that even a young child will know how to use it. Stay away from complicated Flash based menus or multi-tiered dropdown menus. If your visitors don't know how to navigate, they will leave your site.
4) Have a clear indication of where the user is
When visitors are deeply engrossed in browsing your site, you will want to make sure they know which part of the site they are in at that moment. That way, they will be able to browse relevant information or navigate to any section of the site easily. Don't confuse your visitors because confusion means "abandon ship"!
5) Avoid using audio on your site
If your visitor is going to stay a long time at your site, reading your content, you will want to make sure they're not annoyed by some audio looping on and on on your website. If you insist on adding audio, make sure they have some control over it -- volume or muting controls would work fine.

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1. Use "Alt" attribute for images. Some users may not be allowing pictures to show up.
2. Ensure that the web page loads fast (typically withing 5-6 seconds). A slow loading page is very likely to take the visitors away.
3. Use matching colors that are nice to see.
4. Make the web page SEO friendly, else search engines may not find it.

This are some great rules to follow. Nice little article.

You still won't be able to determine that because people have different connections speeds and in different locations.

I know I have mentioned this before ... but I figure it can't hurt to mention it again.

Do not assign absolute sizes to the fonts being used. Instead, choose to use either percentages or the "Normal, Small, x-small, larger" types of designations.

Not all of us use browsers that can override the size a site's fonts are set to. And there are more & more (it seems) visually impaired people accessing the net for their info and/or entertainment etc.

Also ... either provide a choice of background & font colors that a visitor can select ... or ... be very careful on assigning the colors. There are sites out there that provide samples & ideas on what colors can be used for the visually impaired.

I am moderately visually impaired ... and an example of what I mean ... red fonts on a black background ... all I can see is total black. Grey on white ... can only see white.

If I encounter a site that I encounter a problem with ... if it contains unique or hard to come by info then I will usually highlight the whole page and I get the white on blue. But if its one of a multitude of sites with the same info or whatever ... I just quickly move on to a more easily seen & read site and you've lost me as a visitor.

Just something else to keep in mind.
Peter

I think, one need to take dial-up speed into account when designing a web page. This is because several people use dial-up as an alternative to cable or dsl. A page should load quickly enough when using dialup connection.