creating visual editor

Why not use the same visual editor that the Dashboard uses?

I’ve never done it, but I guess you just need to link to the TinyMCE JavaScript code. IIRC it’s in a folder something like:

http://www.yoursitesurl.com/wp-includes/js/tinymce

The TinyMCE documentation is at:

http://www.tinymce.com/wiki.php

HTH

PAE