For every single blog reader, the sidebar is one of the most used elements on a page. Contrary, for many bloggers, it is the least thought-of part of their blog.
In this article, I aim to discuss and help you improve your current sidebar.
Navigation
The most common and most important use of the sidebar is for navigating a blog. The ideal sidebar should provide the right amount of tools and information to navigate to common places easily - neither too few nor too many.
A totally-new visitor to your blog should be able to use your sidebar as they can on any other blog. For this reason, it's important to stick with what is generally accepted and be as universally-uniform as possible.
A useful item to have on your sidebar is a list of the most popular posts or the most recent. Generally, I provide the most recent posts, because the popular posts don't change that often - regular readers will prefer to see fresh content, rather than the same articles all of the time.
Subscription
At the top of most sidebars is a section about RSS-subscription. Although this doesn't help the visitor with navigation, it does remind them that they can subscribe if they want to - every time the reader wants to use the sidebar, they will immediately see the subscription options.
I would recommend making subscription opportunities a clear and major section of your sidebar. WordPress, by default, will have some RSS-links under Meta in the sidebar - these are hard to see. For maximum exposure, you should try to use the RSS icon somewhere and possibly provide more information about subscription.
Look how ProBlogger's RSS subscription information is distinguished from the rest of the sidebar, and makes use of colour:

Advertising
Many bloggers like to earn some money from their blog via advertising. Commonly, bloggers will place adverts, from a service like Google Adsense, into their sidebar.
There are a two main advantages to placing adverts in to the sidebar:
- The adverts will be noticed whenever the visitor wanted to use the sidebar, increasing exposure; and
- The adverts will not interfere with the other content, or other elements of the blog, making it appear ideal.
To get a good click-through rate, adverts ideally will be placed somewhere high in the sidebar - usually above the fold. But, there is a disadvantage to this: some navigational elements of the sidebar are pushed further down - below the fold.
When you advertise in your sidebar, you should try to keep the navigational elements as prominent as possible, and towards the top of the sidebar. The navigational elements shouldn't be broken up by advertisements, as this would disrupt the visitors' ability to navigate your blog.
You may want to consider adding another sidebar for advertisements and less-important elements, while keeping the important navigational elements together. See The Benefits of Having Two Sidebars.
A Good Sidebar = A Good Blog?
Hopefully, you've read this article and made some decisions about the future of your sidebar. Obviously, there are more factors to consider, and I will enjoy hearing about what you think is most important.
If you do implement the suggested changes, I hope it will improve you're readers' ability to use your blog.


Sidebar: The Spine of your Blog | Making the Web…
For every single blog reader, the sidebar is one of the most used elements on a page. Contrary, for many bloggers, it is the least thought-of part of their blog….
STUMBLED!
Good tips, a lot of blogs load their sidebars up with ads or social media widgets. Sometimes too many.
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