How can I upload plugin in my free WordPress blog?
Plugins aren’t permitted in blogs hosted on wordpress.com:
http://en.forums.wordpress.com/topic/how-to-install-plugins-in-wordpress-1
To install a plugin on a self-hosted WP blog:
http://remarkablogger.com/2012/01/30/install-wordpress-plugins/
plugin is not permitted on blog wordpress
using you own hosting if will instal plugin