Easily, one of biggest mistakes webmasters make when first starting out on web is in design of their site. This is extremely understandable, considering that, in brick and mortar world, a business's success is often dependent on it's appearance. The more money put into look and design of a business, better it often does.Unfortunately, this doesn't completely transfer over into world of web. In world of web, there is a huge difference between creating an aesthetically pleasing site, and creating a site that is going to be functional and have best possibility for success.
All too often, when people first begin on web, they design their site as if to be a work of art. Making sure it has lots of beautiful graphics, fancy javascript, flash, etc. While all of these things can definitely create a beautiful site, they are also some of biggest hindrances to a business's success.
On net, there are two key things a webmaster must always keep in mind when designing a site; visitor and search engines. If a visitor has to wait to long for a page to download or a search engine can't properly index a site, it doesn't matter how beautiful and informative site is, it will not generate business needed to survive, much less excel.
Let's look at a few of most common things you should be aware of.
*Page Size*
While broadband access is gaining ground, at least half of all internet users still use dial up connections. This means that majority of a sites visitors will be downloading pages at about 3-4 kilobytes per second.
It is estimated that if a page doesn't load within 8-10 seconds you will lose 1/3 of your visitors. That means that a page should not be any more than 30 kilobytes total including text, graphics, html, javascript, etc.
Logo's, backgrounds, and other images, are great, but if they are causing your pages to load too slowly, they are doing you more harm than good. Quite honestly, your visitors do not care about your logo, graphics, backgrounds etc. They are there for one reason and one reason only....to see what you can offer them.
If you must use graphics keep their file size as small as possible by optimizing graphics to utmost extent possible and keeping image size small.
*Splash Pages/Flash Intros*
These are bane of internet. If you have a splash page whether its made up of a large graphic or a pretty flash intro, you are crippling your chances. Design firms often love to talk their clients into these pages because they get to be creative (oh..and charge more).
The truth is, creating one of these pages as entrance way to your site is one of single worst things you can do. Visitors hate splash pages, because they often take too long to download and they don't provide with visitor with anything. Remember, visitor is there for one reason, to see what you have to offer them and get information they are seeking. A huge graphic doesn't answer any of their questions, it only delays their search.
A Flash into is much same, while it will generally download very quickly, it still delays visitor in finding what he or she is looking for.
One of biggest rules you should remember is to keep amount of clicks a visitor must make to get to quality information down to a bare minimum. With every successive click a visitor must make, there is more of a chance he/she will give up and go somewhere else.