While blogging, sometimes bloggers do feel that although they have started a blog entry, but this is not the correct time to publish it (like if insufficient data is available at that time or if the post becomes more meaningful only if posted at a specific date or time), so at that time there’s a feature given by Blogger that can be utilized.
First of all write your blog post as usual.
Then before you publish the post, click on the “Post Options” link above the “PUBLISH POST ” link.
Now change the “Post date and time” default values, by some Future Date & Time, and that’s it, now the post will be published only on that date and time.
You can read more blogger tricks and tips HERE