The mobile site editor works according to the exact same principles as the desktop editor with regards to page structure, design and modules. New readers should start reading the desktop manual to get a hang of how things work on the mobile channel as well.
How to Build up a mobile page
When working with mobile content remember that visitors will see your site on a relatively small screen. A good tip is to not to clutter your pages with too many elements and too much text. Make some space on your pages. Less is more and keeping things simple will help visitors to navigate through your site easier.