The advantage of showing related article to your post is it will help your readers find more information related to the topics. This is base on label or category. This is usually put to the end of the article. After your visitors finish read your article, they will find some links that related to the post base on label or category.
Here's the tutorial to create "related article to your spot":1. Login to Blogger
2. Go to "Layout-->Edit HTML"
3. Click on "Expand Widgets Template" checkbox.
4. Then download THIS SCRIPT or HERE.
5. Open it then copy the scripts.
6. Paste the script after this code : <data:post.body/>. If you have "Read more widget" you will find two codes. Put it under the first code.
7. Save your template.
Good Luck...