When i got the hang of using Ghost platform for my blog, I decided the best way to learn more about ghost was to build a simple theme for my blog. I took the basic theme Casper and built onto it to make it better for me. I added in a sidebar, search box, changed the header, and added disqua in for the comments.
It was a lot easier to create a theme than i thought it would be. It's currently the theme for this blog. I have added it to github if anyone wants to download it and do whatever they want with it.
My Simple Theme: github link.