Make sure your blog name is spelled correctly on your Entrecard, banner or logo.
Do not place the Entrecard widget at the bottom of your blog or bury it in a mass of 125x125 pixel ads. This is disrespectful to your advertisers and to your visitors. You cannot make anyone read your blog, but you can aggravate everyone that stops by.
Select an engaging picture that is related to the theme of your blog for your Entrecard, banner or logo. If you feel that a come-hither look or an anime is the best representation of your blog, no problem.
Badges, banners, 125x125 advertisements, contextual ads, social networking widgets and affiliate links are most effective when used in moderation. Your blog should not look like Las Vegas on steroids.
The most important real estate on your blog is what may be viewed without scrolling. Do not devote this space to a huge header image or a block of advertisements. You want your blog to load and people to see what your blog has to offer before they click off.
Before you change anything in your template or upgrade to a new software version, back up your template, databases and content. Do not lose three years of content because you did not.
Nothing should play automatically when you open your blog: no music, no video, no sound ad, no virtual assistant, nothing.
Whenever you change your template, make sure that you view your blog in Mozilla and IE browsers. I had this wonderful three-column layout for WordPress, but when I looked at my blog with Internet Explorer, the third column dropped to the bottom of the blog.
Have you spotted an error lately that is not on the list above? Please share if you have.