Add a Commente

I have very hard problem. I don’t know where I should klick on, that I can give then “Add a Comment”. I can do just, when I am log in under Name, then it is working, but otherwise it doesn’t work, I really want to know how can I do it. I am hopeless, please if you know how, help me.

I want, that it can be like:
for example (bottom=> "Add a Commente"): http://www.daehwang.com/gallery/main.php?g2_view=dynamicalbum.UpdatesA lbum