Change the add content look and feel for an specific content type? So, I would like to change how the Add Content form looks like. Right now the user sees it like this (everything's in spanish, sorry)



But I would like to change it to something like this (all text in spanish again, sorry)



The text in grey would be the latest saved node, the button on the right ("Agregar Siguiente") acts like the "save" button, but it comes back immediately to this same page.

I know I would have to develop a Module to do this, could you direct me in the right direction to do something like this? Thanks in advance.
You will want to create a theme override template for that content type for the edit mode. Then you can style it how you want. See this link for more information about how to do this:
https://www.drupal.org/node/1142800#comment-4433994