Hello Gitit,
why would you suggest steps, that he has already described as done in his post? 
Hello Pratichi,
do just want to get rid of the navigation panel completly? Than you could change the layout of the page. On the right side you should see the current layout with the navigation area and the content area side by side (red thingy). When you change the layout to "1 Column", the navigation panel should disappear in your preview (and in the portal, too of course^^).
The "visible"-box needs to stay unchecked, too. 
Regards,
Steffi.