Adding navigation buttons to twenty twelve theme on attachment pages

Hello – I am trying to figure out how to add navigation buttons for my attachment pages in the twenty twelve theme. If I add a gallery to a post it give me forward and back navigation buttons to move through the images in the that post only. I would like to have these navigation buttons so that a person can scroll through all of my posts. IE: I make a post that only has one picture (there are some on the page if you want to look) – when you click on that picture – I want it to go to the attachment page, but I want the attachment page to have navigation buttons going to the next and previous POST from the blog – can anyone help me figure this out?

URL: https://www.daily-mash.com/wordpress2/

thanks in advance for the help!