Instructions
Scroll over to "Playstation Network" from your PS3's main XMB menu and select "Sign In."
Scroll over to "Friends," highlight your User ID and press "X."
Select "Comment" from the drop-down menu and press "X" to edit it. Type whatever you want here using the pop-up keyboard.
Select the yellow "Symbols" button in the lower-left corner to add any special symbols. Select "Enter" when you're finished and click "OK" to save.
Scroll left on the XMB menu to "Settings," choose "System Settings" and select "System Language." Choose a language with special symbols, such as Chinese or Japanese, and go back to your comment. The keyboard will now have many new symbols to modify your comment further.