Font style is almost as important as color. The rule of thumb is to use a non-serif (Arial, Verdana, MS Sans Serif) for pages that will be read online. Serif fonts tend to be distracting to the eye and more difficult to read on a monitor. However, serif fonts are recommended for documents that will be read primarily in hardcopy version. A lot of "do-it-yourself" web pages still use the Times New Roman as the default font. Change it. Your page will look more polished and professional, and, as a result, will be easier to read.
Pay attention to font size as well. If the text is too small, it is hard to read – that’s pretty obvious. But large font can also be distracting in that a person with normal (or corrected) vision will have a hard time adjusting to the larger sized font. For text, stick to between 10 and 12 point font.
Please, please, please… stay away from "cutesy" fonts unless you are creating a child’s web page. I find it hard to take a page seriously if it is designed using Comic Sans MS font!
4. Not Enough "White Space"
Web pages that are designed to convey information must depend on words to accomplish that task. There’s no argument there. But too many words can overwhelm the reader and negate the entire purpose of the site. Never, ever publish a website with one solid page of text. Text should be "chunked" – that is, broken down into manageable pieces – allowing for a break between pertinent thoughts. Create sub-heading titles. Utilize bullets and other formating tools. Use bolding and italics to emphasize important points. If appropriate, use text boxes and graphics to further break up the page. Make your page "reader friendly," and more people will read it all the way through. A huge chunk of text is a guaranteed turn-off.
5. Overdone "Flash"
Okay, I will admit, a little Flash, well placed can beef up a website. But, if I try to open up a website that is so heavily laden with Flash that it takes more than a minute to load on my "whiz-bang" little laptop, I am going to close it! There are few things more frustrating to me than waiting for a website to load. I am not a patient person, and Flash does not impress me, at all! If it makes sense, and is quick to load, okay but, if you are only using it to impress, skip it.