CakePHP Debug

Set 
Configure::write('debug',2); /* file://app/config/core.php
This will display basic debugging information like SQL dumps etc. If you can see the error message, fix it.


Also you may use this statement in your view file:
pr($this->validationErrors);
It shows all validation errors. This helps a lot in debugging cake.


A very helpful article I found:
CakePHP Tips

CakePHP Form Textarea Input Size

Default cake css defines all text inputs as having 
width 100%, so if you don't change that then the physical width of the 
textbox will not depend on the size attribute. 


Read more here.
Thanks.