1. Don’t use auto-loading background or any music, blinking or scrolling text, and animated GIFs.
Remove it all. Not only is it annoying for many visitors, but it distracts them from doing what you want them to do. Readers who are assaulted by blinking ads are more likely to leave the site immediately without clicking on anything, and are far less likely to bookmark the site, return to it, link to it, and recommend it. Besides that, visitors who have slow connections may resent that you wasted their time by forcing them to load animations and music files against their will.
2. Don’t use light background, or dark text on a dark background
It’s hard to read text on the background images that have wide mixture of light and dark; any background images should be simple. You can improve readability of the text on a background image by increasing the text size and/or making it bold.
3. Don’t type more than a few words in ALL CAPS.
Words that are in ALL CAPS draw attention to themselves because they seem different from the small letters around them. But if you type everything in all caps, then you will completely lose the effect, since everything looks the same and none of it looks important.
4. Don’t underline words if they’re not links.
Most of the time, something that’s underlined is supposed to be a link. If you underline gratuitously, readers will be annoyed when they try to click those underlined words and discovered that they’re not really links. Instead of underlining the words, you can use italics or bold to emphasize something.
5. Don’t flood your website with tons of widgets
You don’t actually need to use all of the widgets so it is best to keep things organized. Your readers don’t (in most cases) need to see your social profiles that you’re a part of, so leave them alone and stick to the things that matter most for the user experience on your website.