Full Width POSTS not PAGES

[dailyrunner]

So I was instructed by a member of this forum to create some sort of template for posts, and use the Full Width Template for PAGES as a starting point.

These is a bit overwhelming for me, so my first question is:

Where do I start? How do I create a template for posts thats different than for pages?

once the template for posts is made, I understand I save it to the theme folder on my server, but will the template just show up under the Edit Posts interface?

Basically, theres an attributes box under the Edit Pages dashboard interface, but there isn't one currently for the Edit Posts dashboard interface. Do I need to go back in and edit code in other files?

Please help, I have no idea what I'm doing when it comes to this level of customizing.

Thanks