I was looking for a way to use snippets of my blog posts in the home page instead of the full post. The solution is to add the more tag
<!--more--> tag after the last word you’d like to see in the snippet. It’s simple yet very useful and I started using it right away. This should be added in the text (HTML) mode and not the visual mode in the WordPress editor.
Update: Found two other simpler ways of doing the same without typing anything. There’s an icon in first row of the post edit box in Visual tab which does it for you. Otherwise just place your cursor at the place where you want the more tag to be inserted and press