Link From 404 Pages: No one likes error pages and that includes your readership. You can make your error pages a positive experience for your audience, meaning that you can benefit from these pages. You should see this an unique chance to redirect some traffic to important areas of your blog by making sure your 404 error pages are user friendly. You can modify your 404 pages in WordPress quite easily and you can do anything including adding your own links. Just add the content and links you want to the 404.php file.
Whatever be the case, you shouldn't let your blog's error pages sit and collect dust; make them work for you.
Ease of Access: Your number one priority should be to get your important pages and posts out in front of your readers; don't bury them in deep links. Your most critical articles should not be further than two clicks from your main page, both from an SEO viewpoint as well as user happiness. Pages that can easily be found from the main page are preferred by search engines.
Like many other blogs do, you can include a menu in your sidebar that has a list of all your popular posts. So, without forgetting this, simply choose all the pages that are most important on your blog and link to them from your main page. Using a plugin means you can do this on autopilot or you have the choice of doing it by hand.
Create a Series: Writing a series of posts is a simple but effective way to set up a large number of relevant links from one post to another. When you post the first article in the series, you will naturally create a link to the second and so on. All you need to do is take a long article and divide it up into smaller ones, meaning you don't even have to take the time to create a special one.
Last but not the least; try adding internal links to the first few paragraphs of your blog post as it can help you increase the click through rates from RSS readers. Your goal as a blogger should be to provide valuable content, good navigation and an organized blog. All the links you have on your blog should provide your users with a means to reach more interesting and valuable articles.