Prioritize Internal LinkingUse the tag and category features in your blogging application to easily find content by keyword that you published in past blog posts. Create a list of important keywords that you should use as tags, labels, or categories (depending on which blogging application you use), and every time you write a post with one of those keywords, link to the main tag, label, or category page within your post. Try to include links to relevant posts within your blog post text whenever you can. Internal linking is one of the best ways to keep people on your blog longer.
Use Tools to Automate ProcessesThere are a variety of plugins and tools that make it easy for bloggers to automatically include links to related posts at the end of each of their blog posts. This trick is an easy and effective way to get visitors to stay on your blog longer, because it makes it very tempting to click and keep reading about the blog post topic. Tools like the WordPress Yet Another Related Posts Plugin, the LinkWithin widget, or the Outbrain widget offer a variety of options for displaying related content at the end of every post on your blog.
Create a Design that Highlights Great Content
Don't let your best content get buried in your blog archives. Instead, create a "Best of" page and include links to all of your best posts. You could also create a frequently asked questions page and link to blog posts that answer the questions.
The design of your blog can also help to highlight important content. For example, most blogging applications make it easy to add a "Popular Posts" widget to your blog's sidebar. You might even be able to easily add a feed of the most recent posts from specific categories on your blog to make it easy for people to find content related to niche topics.
If you write about a variety of niche topics related to a broader topic, consider using a magazine-style blog theme or template that mimics the look of media and newspaper sites. These templates show snippets and links to a wide variety of posts rather than just the most recent 5-10 posts that traditional templates typically offer.
Develop Navigation that Encourages Browsing and Searching
An often overlooked but essential part of keeping people on your blog longer is the navigational structure of your blog. Use a simple structure in your top navigation bar, and offer a sitemap for more detailed browsing. Make it easy to find your sitemap, frequently asked questions, and best of posts (as discussed above).
It's also extremely important that your blog includes an easily accessible search box, so visitors can search for more content using keywords. However, not all search tools are equal. Test the search tool on your blog (if you already have one active), and see what results you get. If you're not happy with the results, you can bet your visitors won't be happy, and you've lost the chance to keep them on your blog longer. If necessary, consider using third-party search tools such as Lijit or Google Custom Search.