Blog Tricks, how to remove the navigation bar in your post in 10 seconds?

Press Customize tab, press Edit HTML. Copy paste the following line into the css code.
#navbar-iframe{display:none!important;}

In the future, if blogger updates the template, the id "navbar-iframe" may change, you need to view your page's source code (how?), and find the corresponding id.

Notice removing the navigation bar is violating the agreement when you signed up to blogger, so I still keep it there.