Mistakes that are happening around Web designing in internet:
1. The user must know what the site is about in seconds: Attention is one the most valuable currencies on the Internet.
If a visitor can not figure what your site is about in a couple of seconds, he will probably just go somewhere else. Your site must communicate why I should spend my time there, and FAST!
2. Make the content scan able: this is the Internet, not a book, so forget large blocks of text. Probably I will be visiting your site while I work on other stuff so make sure that I can scan through the entire content. Bullet points, headers, sub headers, lists. Anything that will help the reader filter what he is looking for.
3. Do not use fancy fonts that are unreadable: sure there are some fonts that will give a sophisticated look to your website. But are they readable? If your main objective is to deliver a message and get the visitors reading your stuff, then you should make the process comfortable for them.
4. Do not use tiny fonts: the previous point applies here; you want to make sure that readers are comfortable reading your content. My Firefox does have a zooming feature, but if I need to use on your website it will probably be the last time I visit it.
5. Do not open new browser windows: I used to do that on my first websites. The logic was simple, if I open new browser windows for external links the user will never leave my site. WRONG! Let the user control where he wants the links to open. There is a reason why browsers have a huge “Back” button. Do not worry about sending the visitor to another website, he will get back if he wants to (even porn sites are starting to get conscious regarding this point lately…).
6. Do not resize the user’s browser windows: the user should be in control of his browser. If you resize it you will risk to mess things up on his side, and what is worse you might lose your credibility in front of him.
7. Do not require a registration unless it is necessary: let’s put this straight, when I browse around the Internet I want to get information, not the other way around. Do not force me to register up and leave my email address and other details unless it is absolutely necessary (i.e. unless what you offer is so good that I will bear with the registration).
8. Never subscribe the visitor for something without his consent: do not automatically subscribe a visitor to newsletters when he registers up on your site. Sending unsolicited emails around is not the best way to make friends.
9. Do not overuse Flash: apart from increasing the load time of your website, excessive usage of Flash might also annoy the visitors. Use it only if you must offer features that are not supported by static pages.
10. Do not play music: on the early years of the Internet web developers always tried to successfully integrate music into websites. Guess what, they failed miserably. Do not use music, period.