Installing NextGen Gallery plugin

So I downloaded the NextGen Gallery plugin to my computer, and activated it on my wordpress account, but I can’t figure out how to install it in my FTP. I used these directions as a guide: http://wordpress.org/support/topic/plugin-nextgen-gallery-how-to-activate-gallery-carousel-template?replies=3

but those directions aren’t helping. My host is godaddy.com and when I try to create a new folder to name “nggallery” I can’t. I can’t create a new folder at all. Any suggestions?