Now, enter a secret key. The word you choose should be hard for others to guess but easy for you to remember.
One the secret key is entered, just click on save and the mail icon will turn to this.
You can post an article of upto 10MB using email posting method.
You are done!! you can post directly via mail without logging in to blogger.com
By Default the email posting will be published immediately, if you want to save them as draft or to disable email posting, just click on Settings from Blogger Dashboard, then click on Email&Mobile (You can also setup mobile posting here).
Then, select check-box "Save Emails as Draft Posts" under the Posting Options.
You can save the post as draft and then set a date to automatically publish the post by correcting or customizing it.